# Surf for More Math

## Chapter 5: Number to 20

**Lesson 5: Counting by 2s, 5s, and 10s to 20 **

Use these interactive activities to encourage students to have fun on the Web while learning about number to 20. Students can try these activities on their own or in pairs.

**Goal**

Count by 2s, 5s and 10s to 20.

[C, R, V]

**Instructions for Use**

**Sequence Square** allows students to choose a starting number and the sequence step, and then count by 2s, 5s and 10s. You can also use an Interactive Whiteboard with this activity.

You will choose a starting number and the sequence step (make this 2, 5 or 10). Then click the “Begin” arrow. You will see all the arrows in the sequence that you set up. Click on the starting number and on the number you think is next. Continue until all the numbers have disappeared and the sequence is complete. Click “Main” to choose another sequence.

Try starting at 3 and counting by 2s, starting at 4 and counting by 5s, and starting at 6 and counting by 10s.

**Interactive Hundreds Chart ** is an online hundreds chart that students can use to skip count by 2s, 5s or 10s.

Click on the colour you would like to use. Then decide if you want to skip count by 2s, 5s or 10s. Choose a number to start on, click on that number to highlight it, and then click on every number in your skip counting sequence.