Have the students try to obtain a particular sum with the addends provided. For Example: How can you obtain the sum 8 from the addends you see?

As an extention activity, have the students figure out how many ways there are to obtain a particular sum. For example: How many ways are there to obtain the sum 3? Answer: Two different ways, by clicking on 1 three times, and by clicking on 2 once and 1 once.

Use the Counting Machine to add 8 + 7. The students will need to disect numbers mentally in order to complete the task.