Hundreds chart builds number sense
Building mental mathematics
Using the hundreds chart in your classroom helps build number sense. The hundreds chart, if understood, helps children develop the understanding of a relationship of numbers which helps with skip counting, factors, adding, subtracting, multiplying, dividing, even and odd, fractions, etc.
I have my grade 3 students use their hundreds chart from Day 1 of school. They have a hundreds chart in their math duotang and then when they have marked up one they recycle it and get another. From Day 1 we use the hundreds chart to see what factors there are for every school day. From this we can see patterns and relationships between numbers.
- They become aware that 2 and 5 are factors of 10
- When determining how many twos in 44, they know that there are 5 twos in 10 so for every 10 they count by 5’s and at 40 that is 20 two’s
- From there they count on 21 groups of 2 at 42 and 22 groups of 2 at 44
Many now have gained the understanding of the factors for the multiples of 10 which helps find factors more efficiently.
- On Day 75 of school (January 11th, 2017), many students could tell me they know there are 10 fives in 50
- From 50 to 75 is 25 so that is another 5 groups of 5
- There are 15 groups of 5 or 5 groups of 15 in 75
Through our daily work students have made the connection that when you move to the right within a row numbers increase by 1 and if you move to the left within a row numbers decrease by 1. To add, they understand that if you move down within a column numbers increase by 10 and if you move upwards within a column numbers decrease by 10. With this understanding we can add and subtract using a hundreds chart.
Following many different activities using a hundreds chart, we played a game using a die and a hundreds chart. I gave each student a hundreds chart and I had the die. I modelled how to play with my educational assistant and she showed and explained her thinking on the interactive hundreds chart on my Smartboard file.
The rules are:
- You will have 10 rolls of the die and you must use all 10 rolls.
- You can decide if the number that lands face up on the die when rolled will be given the value of ones or the value of tens.
- The goal is to reach as close to 100 as possible or 100.
- The work will be recorded within a Tens and Ones games chart (see the example below).
Our score was -5 from 100 in the example below:
|1 (first roll player chose 1 as 10)|
|6 (2nd roll, 6 ones was chosen so total is 16)|
|3||(total is 46)|
|1||(total is 56)|
|5 (total is 61)|
|1||(total is 71)|
|6 (total is 77)|
|3 (total is 80)|
|5 (total is 85)|
|1||Total is 95|
I told the students they need to strategize throughout the 10 rolls, knowing if to choose the value to be ones or if to choose the value to be tens.
After the game they were asked to reflect on their decisions to determine if they would have strategized differently at a roll or rolls to reach a score of 100. If we reached a score greater than 100 before or on the 10th roll then we busted and they need to reflect on this as well. This builds mental mathematics as well as allows the students the opportunity to use the 100’s chart.
After we played together, they played independently:
Due to the students having challenges keeping the rows aligned I created a game sheet and have provided this for your classroom use.
Click here to download the game sheet: Game Sheet for Hundreds Chart
Try it with your students
If your students are in Kindergarten you can modify:
- Give each student a number line 1 to 10, a die and some sort of counters.
- Tell them they have 3 rolls.
- After each roll, they need to show the count of the die using the counters.
- Once they have completed the third roll they need to strategize to determine if the sum of all three counts is 10, less than 10 or greater than 10.
- They are not allowed to put the counters along the number line to see.
- What they then have to do is determine if they will choose the sum of 2 rolls or all 3 rolls for a sum of 10 or as close to 10 as possible.
- When this is done, they can lay the counters down along the number line to see if their thinking/reasoning was correct
If your students are in Gr. 1 perhaps you can use half of the hundreds grid, 1 to 50.
If your students are in Gr. 4, 5 or 6 you can use a hundreds chart to 200, 300 or 400 and they multiply the numbers rolled on the die.
Think about the modifications and/or variations that can be made to meet the needs of your students.
I look forward to hearing how it went with your students! Leave a comment below with your questions and comments.