CK-12 Foundation
Ck 12: Elem Math: Finding the Subtraction Sentence by Pattern Numbers Up to 20
[Free Registration/Login may be required to access all resource tools.] The video shows how to find a pattern in a series of subtraction problems to determine the missing problem in the set. The video is followed by additional problems...
CK-12 Foundation
Ck 12: Elem Math: Completing the Addition Sentence Sums to 20
[Free Registration/Login may be required to access all resource tools.] The video shows how to count backwards to determine the missing number in an addition problem. The video is followed by practice problems to assess student...
CK-12 Foundation
Ck 12: Elem Math: Completing the Subtraction Sentence Numbers Up to 20
[Free Registration/Login may be required to access all resource tools.] The video shows how to use a model to determine the missing number in a subtraction problem. The video is followed by practice problems to assess student...