CK-12 Foundation
Ck 12: Elem Math: Mixed Operations Selecting the Incorrect Sentence
[Free Registration/Login may be required to access all resource tools.] The video shows how to add and subtract three digit numbers with two operations in a number sentence to determine which number sentence does not match the correct...
CK-12 Foundation
Ck 12: Elem Math: Filling in the Missing or Sign
[Free Registration/Login may be required to access all resource tools.] The video describes how to determine if a number sentence is addition or subtraction by testing the operation to determine which reveals the correct solution. The...
PBS
Pbs: Commutative and Associative Properties of Addition
Generate equivalent expressions using two additive properties. This video focuses on using the associative and commutative properties of addition to combine like terms, simplify expressions, and create equivalent expressions.