Counting to 100 and 1000

The focus of this unit is counting in a variety of ways - grade 2 to 100 and grade 3 to 1000. We will work specifically on counting by 1, 2, 5, and 10. Grade 3 will also explore counting by 3, 4, 25, and 100. Knowing the number sequence forward and backward is an important part of understanding numbers and being able to perform operations (addition, subtraction, multiplication, and division). Understanding counting can also help students to understand place value like knowing the next number after 109 is 110, not 200. Being able to skip count can help to more efficiently count objects (and money), calculate, and notice patterns.

Topics covered include:

• counting forward and backward to 1000 by 1, 2, 5, 10, and 100 starting from any number up to 1000 (grade 3)

  • the words "starting from any number" are important to note here. Students need to notice patterns when starting from a number that is not a multiple (like: count by 5 starting at 7, or count by 10 starting at 238)

• counting forward and backward to 200 by 1 and to 100 by 2, 5, and 10 (grade 2)

• correctly counting across decades and centuries (for example: 78, 79, 80, 81 or 198, 199, 200, 201)

• counting forward and backward by 25 starting at multiples of 25 (grade 3)

• identifying and correcting errors in a given counting sequence

• determining the value of a given set of coins (pennies, nickels, and dimes for grade 2, quarters and loonies for grade 3)

• estimating a given quantity by comparing it to a referent (a known amount, so for instance if you know that one pile has 10, how many might be in the other pile?)

• identify even and odd numbers (grade 2)

• grouping objects in different ways in order to efficiently count them

Some Ways to Practice at Home:

• Give your child a big pile of objects and ask them to count them for you. Have them count out 10 or 100 first so they have a referent, and then make an estimate of the entire pile.  Then count the pile. As they count, encourage them to find ways to keep track and to think about efficient ways to count. Be sure to have them explain to you how they counted.

• Have your child count your change. This is excellent practice for skip counting, and if you have multiple types of coins, it's good practice counting on from a number.

• Ask your child to estimate an amount (like how many beans will fit in the cup, how many people at the hockey game, how many candies in the bag). Talk about what numbers would be reasonable (10 beans in the cup is probably not reasonable, nor is 900). Give them a referent by showing them what 10 or 100 of that item looks like and then have them refine their estimate.  Don’t focus on trying to get the exact number, focus on making a reasonable guess.

• Play board games like Monopoly, but when you roll the dice you need to skip count by a given number as you move.

• Go for a walk and practice skip counting by a given number each step.

• Find things around the house or in the community and count them based on the way they are arranged (maybe in groups of 2 or 5 or 10).

• While driving in the car, have your child count the headlights they see on the on-coming traffic (counting by 2s).

• Play with a calculator. Type in a 2 or 3-digit number, then press + 5. Press the = button. Then predict the next number and press = again. Keep predicting then checking until 1 minute runs out. You can also use the - button to practice counting backwards.