To expand children's thinking process and help them "see" groups, ask questions like:
- "7 and how much more make 10?" "70 and how much more make 100?" "700 and how much more make 1,000?"
- "10 and how much more make 15?" "10 and how much more make 18?" "10 and how much more make 25?"
- "17 and how much more make 20?" 87 and how mcuh more make 100?" "667 and how mcuh more make 1,000?"
- "How far is it from 6 to 10?" "How far is it from 89 to 100?" "How far is it from 678 to 1,000?"
- "How many 10s are there in 70?...100?...200?...340?...500?... 1,000?...1,000,000?...a quadrillion (there are 15 zeors)?"
-"How many 4-person teams can you make out of 12 kids?...20 kids?... 100 kids?...50 kids?"
- "How much is 5, four times?...ten times?... a hundred times?... a thousnad times?"
Notice how these questions focus on the number 10, multiples of 10, and powers of 10. These exercises can all be done by counting mentally, and do not require students to do pencil-and-paper computations.