## Problem Solver +/- (AS)

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

### Other Examples:

• Asked, "What's 28 + 35?", incrementer thinks: "20 ... 30, 40, 50; then 58, 59, 60, 61, 62, 63."
• 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!"
• Combining tens and one: "20 + 30 = 50.”
• A child thinks “8 + 5 is like 8 plus 2 and 3 more, so, it's 13.”

These activities challenge children to solve all the addition and including some multidigit problems.  Children continue to build and use sophisticated  strategies, and can discuss the relationship between problems and operations. For example, for a Separate, start unknown, problem such as "You had some candies, and you gave your friend  8 , now you have 5. How many did you have to start with?" a child might say, "It is like a subtraction problem, but you don't know the whole, so you got to add 8 and 5."