Central Idea
"The operations of addition, subtraction, multiplication and division, as well as fractions, are related to each other and are used to process information and solve problems."
Tuning In
Exploding Dots  A crazy machine that can help us find out more about Place Value and other number systems! Try machines created by James Tanton (our friend in the video to the right) or create your own machines. What patterns do you see? How do these machines relate to number systems in the real world?
Place Value Prior Knowledge  To find out what we already know about numbers, pick a challenging number that you think you know quite a bit about and show different ways that you can represent that number and round it using the sheet attached. Place Value Prior Knowledge  We may know more about number patterns than we think. Use the sheet provided to share what you already know about patterns in numbers and number systems. You can also share any questions that you have going further. 

Rounding Whole Numbers  Using the calculators / money / base 10 blocks, or any other place value material, practice making numbers and rounding them to the nearest ten / hundred or even thousand. Complete the sheet attached to show what you know about rounding and how we use rounding in our day to day lives.
Number Hunt  There are numbers all around us. Using the sheet provided, explore the class and the surrounding area to see if you can find any numbers that fit the description. Don't forget to say where you saw the numbers and to try and find numbers from as many places as possible. How Much is A Million?  As we begin to recognize bigger and bigger numbers, we may start to lose track of just how large the numbers actually are. Read the book, How Much is a Million, by David Schwartz. This book shows a lot of real world examples relating to the extremely large number  1,000,000! 
Finding Out
Investigating Other Number Systems  Take a look at the watch to the left. Is there something different about the numbers on the face of the watch? What is interesting about the number system on the face of the watch? Are there other number systems? What do they have in common? What is different about them?
Patterns in the Base 10 System  Using some of the concrete materials below, explain what patterns exist in the Base 10 number system. How are the tools used? What do they have in common? Skip Counting  Skip counting is easy, right? 2, 4, 6, 8, 10.... No problem! With a partner, practice your skip counting and see how you can make things more challenging. Forwards, backwards, by 10's, 5's, 12's, 10,000's? Start at random numbers, include decimals and fractions  negative numbers... yes, skip counting can be quite a challenge. What patterns can you find when you skip count while looking at a hundreds or thousands chart? Try to plot some of the numbers on a hundreds chart to see if there are visible patterns. 
Website Search  to find out about place value and rounding, it is important that we use different tools to learn more. There are videos on YouTube, experts we can speak to, and there are websites like Math is Fun and BrainPop Jr. where we can find out more.
Calculator Go Fish  Check out our games page for more interesting games relating to Place Value and while you're there, be sure to check out the instructions on how to play Calculator Go Fish.
Say a Number / Write a Number  To continue to practice our numbers, we can use the calculators to play the game, Say a Number, Write a Number. With a partner, one person says a number out loud while also typing the number into their calculator. Your partner also punches the number that was said into their calculator (without looking at your screen). When both of you have put in the number, check the screens to make sure you have written in the same thing.
This game can get more challenging depending on how large the number you are saying. To create more of a challenge, try larger numbers, numbers with decimals, numbers with lots of Zeros spread throughout, and you could even try saying numbers with number nicknames, or in another language.
Calculator Go Fish  Check out our games page for more interesting games relating to Place Value and while you're there, be sure to check out the instructions on how to play Calculator Go Fish.
Say a Number / Write a Number  To continue to practice our numbers, we can use the calculators to play the game, Say a Number, Write a Number. With a partner, one person says a number out loud while also typing the number into their calculator. Your partner also punches the number that was said into their calculator (without looking at your screen). When both of you have put in the number, check the screens to make sure you have written in the same thing.
This game can get more challenging depending on how large the number you are saying. To create more of a challenge, try larger numbers, numbers with decimals, numbers with lots of Zeros spread throughout, and you could even try saying numbers with number nicknames, or in another language.
Concrete
All of the concrete materials below can be used to help solve problems when working with numbers. Some are better for working with larger numbers, while others are better for working with smaller numbers. Listed below are some example games and lessons where you might use these tools.
Base 10 Blocks
 the ultimate tool for learning about place value  can be adapted for use in addition and subtraction, multiplication and division and even fractions 
Expanded Notation Cups
 a fun tool to make to show how the digits in a number can have different values  also great for ordering and comparing numbers 
Tens Frames
 great for subitizing numbers to 10 and 20  helpful for seeing how numbers combine to make facts that are easier to mentally add and subtract 
Place Value Disks
 like the tools above, these are helpful for seeing place value and for working with numbers  useful for seeing how digits differ in numbers  can be a bit confusing because sizes are the same 
Money
 great for learning about place value in a real world context  a good first step into learning about how there are numbers in between whole numbers on a number line 
Place Value Chart
 great to use so that we can see patterns in larger numbers  helpful for naming larger numbers and when working with number nicknames 
Hundreds Chart
 great for looking for patterns in skip counting  helpful for finding numbers when addition and subtracting  can be used with counters (clear)  also helpful when using repeated addition and subtraction (aka multiplication and division 
Calculators
 Calculator Go Fish  Broken Calculator  Rounding Whole Numbers 
Pictorial
Alien Numbers  There are other number systems out there  I mean... WAY out there! If there was an Alien species that visited Earth, what Number System do you think they would use? Create an Alien number system and an explanation of how it is used so that our little Earthling friends can comprehend it!
Place Value Monster  Create a place value monster using thousands, hundreds, tens and ones from our base 10 blocks. See the examples below for inspiration, but try to create something new. Name your monster and find out what special number they represent. 
Abstract
Online Practice  Khan Academy and Prodigy have lots of different questions relating to Place Value and Rounding. See if you can achieve Mastery in these areas. If you can find another site that you enjoy, share it with the class.
Place Value Video  Watch the video to the right to find out more about Place Value. Use our Research Sheet to track your understanding and to write any additional questions you have. Number Nicknames  The Base 10 place value system is used in many different countries and in many different languages. What are the difference and similarities between the way we name the numbers in English versus the other languages we know? Are some languages easier to see patterns within the number system we use? How can we use number nicknames to make finding patterns in our number system easier? 

Rounding Practice  with a partner, try rounding different numbers that you see to the nearest ten and the nearest hundred. Try to find a partner who can challenge you to round more difficult and larger numbers.
Using Rounding to Add and Subtract  So, how can rounding help us in other areas of mathematics? If there is no purpose for rounding, then why would we do it? I am sure that you use rounding to help you with computation, so how do you do it? Is there more than one way?
Using Rounding to Add and Subtract  So, how can rounding help us in other areas of mathematics? If there is no purpose for rounding, then why would we do it? I am sure that you use rounding to help you with computation, so how do you do it? Is there more than one way?
Applying
Finding Large Numbers in the Real World  Go on a number walk to find numbers in the real world. Numbers are all around us. Some big, some small. We can find numbers in everyday objects, even if the number isn't written out. Use the sheet attached to keep track of the numbers you find. You can also use your iPad to take photos. You can even put your collection together using Book Creator.
Rounding SeeSaw Video  There are many different strategies when it comes to Rounding numbers and there is no perfect way to explain how to do it. We have thought about the reason why we round, but can we explain how we round. Using the iPad, try to explain to someone your age the strategies that you use to round. Upload your videos to SeeSaw
Rounding SeeSaw Video  There are many different strategies when it comes to Rounding numbers and there is no perfect way to explain how to do it. We have thought about the reason why we round, but can we explain how we round. Using the iPad, try to explain to someone your age the strategies that you use to round. Upload your videos to SeeSaw
Addition and SubtractionAn inquiry into...


Tuning In
Theories and Questions  as a class, create a list of questions and theories about the Central Idea and Concepts to add to the board. As time progresses, add to the board, or check to see if previous questions have been answered, or if theories have been proven or disproved.
Assessing our Prior Knowledge  To find out what we already know about mental and written strategies, it is important for us to show what we know. Using a mind map and some suggested questions from the teacher, show a variety of strategies for solving the problem given.
Venn Diagram  with a small group, create a poster with overlapping circles, where one circle shows what addition is all about and the other shows subtraction. Where the circles overlap, write down the similarities, if any, between the two. Once your small group has completed the task, join with the rest of the group to put the class ideas together.
Assessing our Prior Knowledge  To find out what we already know about mental and written strategies, it is important for us to show what we know. Using a mind map and some suggested questions from the teacher, show a variety of strategies for solving the problem given.
Venn Diagram  with a small group, create a poster with overlapping circles, where one circle shows what addition is all about and the other shows subtraction. Where the circles overlap, write down the similarities, if any, between the two. Once your small group has completed the task, join with the rest of the group to put the class ideas together.
Finding Out
Subitizing  How do you see the number of dots on the right? Do you see groups of three on the outside with one dot in the middle? Do you see four dots, like on a set of dice, with three dots running through the middle? Draw a picture to show how you see the dots. Share your pictures with others. Does anyone else see things the way you do? How many ways do you think people might see these dots.
More Subitizing  Being able to see numbers quickly, especially by finding common groups is a very important skill that takes practice. Seeing 10s and making tens is very important to being able to add and subtract quickly. Click on the title to find a whole host of great games and lessons that you can work on using subitizing cards as well as 5 and 10 frames. 
Number Talks  Number Talks are short, daily exercises aimed at building number sense. Number sense is the ability to play with numbers meaning you can visualise problem solving, perform calculations quickly, and are flexible with your mathematical strategies. What are some strategies that we know when adding and subtracting numbers within 20? What are some strategies we know when adding larger numbers? How are they the same? How are they different?
Creating Strategies  As a class, do number talks and discuss strategies you are using to add and subtract numbers. Come up with some names for different strategies. Rank your strategies in different situations. Are some better than others? What makes them better? If you come up with a new strategy, you could name it after yourself.
Creating Strategies  As a class, do number talks and discuss strategies you are using to add and subtract numbers. Come up with some names for different strategies. Rank your strategies in different situations. Are some better than others? What makes them better? If you come up with a new strategy, you could name it after yourself.
Mental Addition and Subtraction of Larger Numbers  Below are a series of videos that show strategies we might use for adding and subtracting larger numbers using mental math. The students in these videos are showing their thinking in writing, but by practicing with larger and larger numbers using some of these strategies, we can start to manipulate numbers in a way that makes them easier to work with. Subtraction strategies are on the left, addition on the right.
Round the Subtrahend

Round and Adjust


We might use this strategy when we come across numbers that are close to 10's or 100's.
Try these: 139, 248, 618 6328, 7139, 8459 13499, 24798, 31597 

We might use this strategy to make things easier when we would otherwise have to "carry." Helpful for decimals and fractions as well.
Try these: 13+9, 24+8, 68+8 63+28, 74+39, 84+59 144+99, 248+98, 468+84 
Decompose the Subtrahend

Take and Give


This strategy is helpful for removing smaller numbers in manageable chunks.
Try these: 326, 218, 437 4317, 6216, 4728 8337, 9126, 8436 

A helpful strategy if there is enough to give to create nice, round numbers. Also helpful for decimals and factions.
Try these: 16+8, 18+6, 29+7 46+98, 89+65, 146+197 3.76+2.89, 8.9+0.56, 3.8+1.4 
Add Instead

Start from the Left


This strategy is helpful when rounding doesn't make sense. Plus, it's all about adding!
Try these: 2319, 5148, 3427 223219, 351348, 435427 

Going from Left to Right is a much more natural way to add. It's also easier when adding multiple numbers.
Try these: 43+56, 54+35, 24+67 376+523, 274+432, 117+356 23+31+48+42+29+35 
Same Difference

Break one Addend Apart


My personal favourite  a great strategy if we understand moving set distances around on the number line.
Try these: 9328, 7639, 5718 236188, 3456687 

Adding any number to a multiple of ten is easier. Works with all problems and in flexible ways.
Try these: 15+23. 25+36, 37+49 237+314, 456+238, 183+276 0.23+0.57, 1.07+0.68 
Break Apart by Place

Add Up


This strategy is helpful as many of us naturally like to subtract numbers from left to right. You may need a good grasp of integers to do this.
Try these: 7256, 8127, 6328 337159 

Similar to break one addend apart, but with this strategy, we are usually breaking the addend into multiple parts. Helpful for larger numbers
Try these: 258+39, 547+34, 546+28 351+439, 1348+143, 1985+1245 1.09+0.83, 7.06+0.48 
Addition and Subtraction Games  There are lots of different addition and subtraction games. Too many to list here. Check below under our Concrete Materials section and on our Math Games page, to find more videos and games.
Games with the Rekenrek

Games with Dice and Dominoes

Concrete
Tools  With a partner, show how certain tools can help you to visualize and model addition and subtraction in a concrete way. What tools will help you most? Are there certain tools that are better, or worse than others? What happens with the tool you are using as you get into larger and larger numbers?
Many of the tools listed above (in the Place Value section) can also be used when modelling addition and subtraction. Check out the tools below and think about how they can also be used.
Rekenrek
 very helpful for visualizing numbers to 20  see what is missing, see what is there (subatizing)  helpful with a teacher / parent / partner that can help you improve your facts to 20 
Dominos
 another great tool for practicing adding and subtracting numbers, especially numbers within 10  many different games that can be played and changed to increase or decrease difficulty (see above videos) 
Cards
 always great for addition and subtraction games  easily adaptable for making games more challenging / easier  helpful for practicing facts without things getting boring 
Dice
 just like cards, dice are great for fast practice of facts for addition and subtraction  change up games often to get better at all areas of addition and subtraction  use different types of and numbers of dice 
Tens Frames
 helpful for showing patterns in addition and subtraction  great for visualizing Making 10, an important part of mental addition and subtraction 
100 Beads
 also great for showing patterns, especially with repeat addition and subtraction  like Tens Frames, also good for making tens, but further along the number line 
Pictorial
Part Part Whole  When we are adding and subtracting, things can get a little confusing if we do not see numbers lined up in the familiar way. Most of us would have no problem finding the answer to 7 + 2 = ___, but things can get confusing when the question looks more like 7 + ___ = 9, or 9 = 2 + ___. Part / Part Whole is a way of modelling addition and subtraction questions without the need for pluses and minus. Simply identify whether the number you are trying to find is the part or the whole. The picture on the right shows several questions where the Part is missing.
Number Bonds  Number Bonds look similar to Part Part Whole Models, but we would use them for different reasons. It is important that we can break apart numbers in ways that make them easier to add and subtract. Watch the video below to see how using number bonds can help with addition and subtraction. Bar Modelling  Bar Modelling is an excellent way of visualizing problem solving questions. Watch the videos below to find out more. 



Abstract
Kakooma  This game is a great way to practice your addition. The way it works, as seen on the right, is that a puzzle is shown. In that puzzle, there are a series of numbers. One of the numbers in the group is the sum of two other numbers. That is the number you have to click on. Once you have done that for each of the puzzles, the final puzzle (the answer to each one of the sums you made before), is also just like the other puzzles. The goal is to find the sums as fast as possible. Some of the puzzles have 4 in a set, some as many as 9! The great thing about Kakooma is that you are doing LOTS of mental addition to find each answer and sometimes you don't even realize it. There are many more great games on Greg Tang Math.

Khan Academy  You will see Khan Academy on here many times. It is my favourite website for math learning. The reason being, it keeps getting better and students from Year 2, all the way through University can use it. When doing the addition and subtraction questions, Khan Academy asks questions in so many different ways  and unlike sitting down and doing a worksheet  you get instant feedback, you have videos and hints to help you along and there are rewards and points for mastering different skills. Although things look different on each, Khan Academy can be used on both the computer and the tablet. I recommend the tablet, because it is easier to use the scratch pad to work out your answers.
Math Trainer  Practice makes perfect. With the Math Trainers (which can be used for all four operations), we can track our progress and focus our learning on the areas we need to improve. Here is a direct link to Addition and here is a direct link to Subtraction. I recommend setting the timer to 1 minute, with a cut off time of 8 seconds. The Math Trainer really needs a computer to work, as you need to be able to type in numbers quickly. Take a screen shot of your records and share with others! The table at the bottom will show you which areas you are answering well and which you may need to work on.
Math Trainer  Practice makes perfect. With the Math Trainers (which can be used for all four operations), we can track our progress and focus our learning on the areas we need to improve. Here is a direct link to Addition and here is a direct link to Subtraction. I recommend setting the timer to 1 minute, with a cut off time of 8 seconds. The Math Trainer really needs a computer to work, as you need to be able to type in numbers quickly. Take a screen shot of your records and share with others! The table at the bottom will show you which areas you are answering well and which you may need to work on.
Applying
Creating Word Problems  There are many things we can do to create word problems that are more challenging than the standard. As a class, investigate the different types of addition and subtraction word problems, then create some of your own. Rank the word problems that you have created from least to most challenging.
What are the variables that you can change in a word problem to make it more challenging? What problems have you experienced in your day to day life that represent the different types of word problems.
Word Problem Generator  From the same person who brought you Kakooma, here is a site that can help you to come up with some word problems that are not all just "What's the Total?" type questions. Check the images out below to see the different types of questions you might have. Being able to take the question and write it in an abstract way may be difficult to do at first. Try using models to help you figure out what type of question it is.
What are the variables that you can change in a word problem to make it more challenging? What problems have you experienced in your day to day life that represent the different types of word problems.
Word Problem Generator  From the same person who brought you Kakooma, here is a site that can help you to come up with some word problems that are not all just "What's the Total?" type questions. Check the images out below to see the different types of questions you might have. Being able to take the question and write it in an abstract way may be difficult to do at first. Try using models to help you figure out what type of question it is.
101qs.com  Addition and Subtraction are all around us. Often we can find math in everyday situations. On the website 101qs, there are videos and pictures that people have made where they are looking at problems through the lens of mathematics. Try to come up with your own questions in these three act math tasks. What information will you need to know to answer your question?
Multiplication and Division
An inquiry into...
 The differences and similarities between multiplication and division (CONNECTION)
 How to make mental multiplication and division easier by finding different ways to shape numbers (CHANGE)
 The different types of word problems involving multiplication and division (FORM)
Tuning In
Finding Out
Break a Factor into Two or More Addends

Multiply Instead


To start, we might want to practice with smaller two digit factors, or single digit multiplied by two digit,
12 x 6 13 x 8 14 x 12 12 x 13 

When we multiply instead, we should have a good understanding of our multiplication facts.
15 ÷ 3 21 ÷ 5 17 ÷ 3 19 ÷ 6 
Factor a Factor

Chunk Out


When we Factor a Factor, how do we choose which number to factor? How does this make the question easier? And why does it work? Can we do this with all numbers, or just specific examples?
14 x 25 25 x 16 51 x 14 18 x 26 

Chunking out is a very useful strategy, as you can use estimation and work with friendly numbers when dividing. Also, you don't need to be "perfect" in your guesses the first time. This is especially helpful with multidigit division questions.
32 ÷ 3 43 ÷ 4 87 ÷ 8 76 ÷ 7 
Round a Factor and Adjust

Make a Tower


When we round a Factor and Adjust, we always want to try and take "messy" numbers and make them more "friendly." Rounding to a multiple of ten when a number is pretty close is always a helpful strategy. This can be done with all numbers, regardless of the size.
12 x 9 6 x 19 21 x 7 8 x 13 

Making a Tower can really help when you're chunking out. Sometimes, we can make a good guess as to what number to try and chunk out, but other times, it is not so easy. When we make a tower, we can see more clearly the friendly numbers that we can work with.

Halving and Doubling

Halving and Halving


Halving and Doubling can be a useful strategy as well, but does not always work for every number. How do we know when halving and doubling might be a good strategy to use? Why does it make some problems easier to think about?
8 x 13 4 x 17 6 x 13 8 x 25 

Just like Halving and Doubling, Halving and Halving does not work for all numbers. That said, when we do find some numbers that might be useful, we need to be able to identify them.
26 ÷ 4 52 ÷ 4 128 ÷ 8 192 ÷ 24 
Concrete
Tools  As with addition and subtraction and place value, there are many tools that overlap with multiplication and division. Check out the tools below to see how they might help you with gaining a better understanding of "repeated addition" and "repeated subtraction."
Hundreds Chart
 helpful for finding patterns in repeat addition and subtraction  can be used with counters / bears / etc for patterning 
Times Table Chart
 in some people's minds, the only thing that matters when it comes to multiplication (not true)  great for showing what you already know and for identifying what you need to work toward 
Pictorial
Abstract
Going Beyond the Grid  If we look at the times table grid, with all of its numbers, it is very easy to get overwhelmed. All told there are more than ONE HUNDRED numbers to memorize! But there is so much more to multiplication than just what is on this grid. Ask most of your parents what 6 x 5 or 9 x 8 is, and they will give you the answers with no problem, but ask them a question that goes outside of the grid and most will lose their confidence and speed. So, when we look into "memorizing" our times tables, we are actually going to try and find strategies that will help us answer questions quickly up to 10 x 10 and beyond. 
Imagine if we started with nothing. Where would you begin? Would you start with your 6 times tables? Would you start with your 7's? Would you go in order from 0 to 10? Remember that from 0 x 0, up to 10 x 10, you will have 121 numbers to remember. So where do you start?
I think most students would agree that the easiest thing to multiply is ANYTHING x Zero! Why is it so easy to remember, because it doesn't matter what the factor you are multiplying is, If you multiply it by 0 than the answer will be 0! 5 x 0.... 0! 56 x 0.... 0! 1,234,045 x 0.... you guessed it... 0! If we know this, than we can actually start filling in our times table grid and achieve our goal of Going Beyond as well! Let's see what that looks like: 
Notice that we have now actually filled in 21 digits on our times table. This is because we also know that 0 x 5 and 5 x 0, as well as all other examples where we switch the order of the factors, will not change the product.
So, we started with 121 and now we have 100 to go. But what do we do next? Most students would probably suggest that our ONE times tables is the next easiest, because ANYTHING x One is just repeating the number. What's ONE group of Twenty? Twenty! 1 x 7.... 7! 9 x 1.... 9? 432 x 1.... 432! 1 x 8,123,324.... 8,123,324! Let's see what that looks like: 
Again, notice that we have now filled in 19 more digits. Why not 21 like the last time? Well, because we already new what 0 x 1 was, and we already knew what 1 x 0 was.
So, we were at 100 and now we're down to 81! Just look how the number of boxes keeps getting smaller? But what do we do next? It would be easy to say that we just move on to our TWO times tables, and then to our Threes, but is our TWO times table really the next easiest to learn? What about the TEN times tables? Do you see any patterns? 
Multiplying by 10 is pretty easy. It would appear that all we do is add a ZERO to the end of the other factor. However, this is not actually the case. We are actually moving the place value of the number to make it 10 times greater than before.
With questions like 7 x 10 or 10 x 84, this makes it look like we just add a zero, but when we multiply decimals, we can see that is not always the case. 34 x 10... 340! 10 x 9... 90! But what about 16.7 x 10? Our answer is 167. That doesn't end in a zero! We are actually moving our decimal place one spot to the right. This works for multiplying by 100 as well. Instead of moving the decimal one place... we move it two! 34 x 100 = 3400? 100 x 9 = 900 16.7 x 100 = 1670 How much would we move the decimal if we multiply by 1000? What about a million? And now, like magic, we've dropped 17 more from 81 to 64! Now let's look at the TWO times tables: 
We have all been doubling since grade 1, so by now we should be pretty good at it. Up to 10, our doubles are not that difficult. Multiplying by 2 and doubling are the exact same thing.
So now, without breaking a sweat, we're down by 15  and only have 49 left to go. That's less than half of what we had to remember at the start, and really, it hasn't even been that tough. Not only that, but all of the numbers we have worked on go BEYOND THE GRID and that means, not only have we sorted out more than half of the times tables up to 10, but we have figured out so much more. But what do we do next? Whether you're skip counting, or finding half of multiples of 10, the next best place to go might just be the FIVE times tables. Let's see what that looks like: 
Skip counting by fives is quite easy, so many of us will rely on skip counting to answer questions with the five times tables within ten until we have them committed to memory, but there is another interesting thing about five that makes it great to multiply with.
Five is half of ten! Why does that matter? Well, it's easy to multiply by ten right? What's 44 x 10? 440, right? Well half of 440 is 220. So, 5 x 44 is 220! 10 x 8.... 80! 5 x 8.... 40! 10 x 86.... 860! 5 x 86.... 430! This can be a little bit tricky with odd numbers, but the pattern still works! Skip counting is fine, but no one wants to skip count 86 times to find an answer. And with an understanding of our 5 times tables, we're down to 36. Just 36 numbers to remember! And now we jump to 9. And I'll tell yah why. 
There are all kinds of cool strategies for remembering your NINE times tables. Did you know that you can even figure out your nine times tables with your fingers? It's true. There are more ways than just that though. My favourite is to think about multiplying by 10 again. Just multiply the number by 10 instead of 9, then subtract the other factor from your total.
For example... 10 x 6 = 60. 60  6 = 54. So 9 x 6 = 54 There are more ways to multiply by 9 than just the ones listed above. See what works best for you. With that we are down to just 25! And now for something a little different: 
Square Numbers are the product of multiplying the same factors together. So, 2 x 2, or 8 x 8, or 182 x 182. Why do you think they are called square numbers?
Either way, you can see the pattern of where square numbers show up on our times table chart and just like that, we are down to just 20 numbers left. You can see that there is a lot of overlap between the different times tables group, so the more we learn, the more we discover that we have multiple strategies for recalling each product. Almost there... What do you think we could do next? 3? 4? How about double doubles! Or the four times tables. 
The four times tables are really just doubling a number (multiplying by 2) and then doubling the number again (times 2 one more time). So 4 x 7 is like saying 2 x 7 x 2. 7 x 2 = 14 and 14 x 2 = 28.
64 x 4 is like saying 64 x 2 x 2. 64 x 2 = 128 and 128 x 2 = 256. Also, a Double Double is two sugars and two creams in a Tim Horton's coffee in Canada. And then there were 12. And on to the Threes... 
Applying
Creating Word Problems  There are many things we can do to create word problems that are more challenging than the standard. As a class, investigate the different types of multiplication and division word problems, then create some of your own. Rank the word problems that you have created from least to most challenging.
Fractions and Decimals
An inquiry into...
 Parts of a whole (FORM)
 Why we might need part numbers in between whole numbers (CONNECTION)
 Where we see and how we use fractions and decimals in our day to day life (CONNECTION)
Tuning In
Finding Out
Concrete
Tools  there are several tools above that can also be used with fractions. With fractions, there are a lot of specialized tools that we may have never used before. These are helpful for us when looking at parts of a whole. Remember though, we can not know what the fraction is unless we know what the part is and what the whole is.
Fraction Tiles
 very helpful when visualizing how fractions can be part of a whole  also great for seeing equivalent fractions 
Fraction Blocks
 similar to fraction tiles, but can be used to stack and connect fractions together  in that way, they are good for showing equivalent fractions, as well as adding fractions together 
Fraction Circles
 good for showing how equal parts do not always have to be rectangles  great if they do not have any numbers written on them, because 1 circle should not always equal 1 whole 
Cuisenaire Rods
 a great little tool for showing how parts of a whole can change, depending on what the whole is  also good for showing equivalent fractions 