CCSS strategies

Vocabulary:

Level 1 - "direct modeling"; everything physically represented

Count all

Taking away

Trial and error (*)

Matching (*)

Level 2 - "counting" strategies; only one number is physically represented

Counting on

Count down

Level 3 - "convert to an easier problem", then may use other levels or numbers

Make a ten

Doubles +/–n

Rearrange (e.g., thinking of subtracting as finding an unknown addend)

Commutative property

Model how to solve each CCSS problem type using strategies listed. Next class groups will present based on random assignments of types, unknowns, and strategies.

	Result unknown	Change unknown	Start unknown
Add to	count all counting on (varies)	n/a counting on (varies)	trial and error n/a commutative prop.
Take from	taking away counting on/down rearrange	n/a counting on/down rearrange	trial and error n/a rearrange

	Total unknown	Addend unknown	Both addends
Put together / take apart	count all counting on (varies)	n/a counting on (varies)	n/a n/a n/a

	Difference unknown	Bigger unknown	Smaller unknown
Compare	matching counting on (varies)	matching counting on (varies)	matching counting down (varies)

Make example problems for each of the Level 3 strategies.