Composing Numbers

Problem Solver +/- (Composing Numbers)

Solves all types of problems, with flexible strategies and known combinations. Multidigit may be solved by incrementing or combining tens and ones.

Activities

You may see this:

Other Examples:

Asked, "If I have 13 and you have 9, how could we have the same number?", says, "9 and 1 is 10, then 3 more to make 13. 1 and 3 is 4. I need 4 more!"
Asked "What's 28 + 35?", incrementer thinks: "20 + 30 = 50; +8 = 58; 2 more is 60, 3 more is 63." Combining tens and ones: "20 + 30 = 50. 8 + 5 is like 8 plus 2 and 3 more, so, it's 13. 50 and 13 is 63."

Help your student become a(n) Problem Solver +/- (Composing Numbers)

Activities present problems such as those that bridge decades, 77 + 3 and 25 + 7. As always, they use manipulatives and modeling as necessary, until children can solve the problems mentally, or with drawings such as the empty number line. When children can do this, hide those visual models so children build mental models.