Counting by Tens Past 100 and 200

Purpose

To count forwards and backwards by tens.

Materials

None

Overview

Choose a number that is not a multiple of 10. Have children count by tens in unison, beginning with the chosen number. Continue counting in this way past 100. Then say “Switch!” and have children start counting backward by tens from that place. Repeat with a different starting number, but this time, have them count by tens past 200 and then count backward as far as they can. Relate the forward and backward counting to adding and subtracting 10 from any number.

About the sequence

Part 1 counts forwards and backwards by tens, ending at a number past 100. Part 2 repeats the sequence, ending at a number greater than 200. The extension also repeats, ending at a number greater than 300.

Part 1

Let’s count forward by tens from (starting number). When I say “Switch!” we will count backwards by tens.

Example:

54, 64, 74, switch, 64, 54, 44, switch, 54, 64, 74, switch, 64, 54, switch, 64, 74, 84, 94, 104, 114

If children need more practice or are enjoying their mastery, repeat. If children are ready to move on, go to Part 2.

Part 2

Let’s count forward by tens from (starting number). When I say “Switch!” we will count backwards by tens. (Allow the sequence to continue past 200.)

Example:

137, 147, 157, switch, 147, 137, 127, switch, 137, 147, 157, 167, 177, switch, 167, switch, 177, 187, 197, 207, 217

If children need more practice, repeat. Or, when children seem excited for a new challenge, move to the extension.

Extension

Let’s count by tens from (starting number). When I say “Switch!” we will count backwards by tens. (Allow the sequence to continue past 300.)

Example:

249, 259, 269, switch, 259, 249, switch, 259,269, 279, 289, 299, 309, switch, 299, switch, 309, 319, 329