We may earn a commission when you click links to retailers and purchase goods. More info. The world’s population apparently is increasingly using two phone numbers to manage their lives, and that ...

Charlie Bardey shows different ways to make 10 when adding two numbers. Charlie Bardey is planning a picnic for friends. He needs to tally the number of people who would like bananas or strawberries.

Use a double 10-frame to play a game and represent adding three single-digit numbers. Warm up with a Mystery Math Mistake to decompose teen numbers. Use a double 10-frame to represent adding three ...