standard_description: Apply properties of operations as strategies to add and subtract. (Students need not use formal terms for these properties.) Examples: If 8 + 3 = 11 is known, then 3 + 8 = 11 is also known. (Commutative property of addition.) To add 2 + 6 + 4, the second two numbers can be added to make a ten, so 2 + 6 + 4 = 2 + 10 = 12. (Associative property of addition.)
problem_activity: Problem 1
Act 1: Watch the video
Gummy Worms
by Kyle Pearce.
a.   What do you notice? What do you wonder?
b.   How many gummy worms are there in total? Make an estimate.
Problem 2
Act 2: Use the following information to determine how many gummy worms there are in total.
[IMG]
There are 7 of each the yellow & black gummy worms and orange & black gummy worms left in the jar.
There are also 3 yellow & orange gummy worms left in the jar.
Problem 3
Act 3: There are 25 gummy worms in total. Was your answer reasonable? Why or why not?
Problem 4
Act 4 (sequel):
Mr. Pearce eats all of the gummy worms he took out of the jar and a few extra still in the jar. In total, he ate an equal number of each of the 3 colors of gummy worms, a total of 18 gummy worms. How many gummy worms does he have left of each color?


aligns: no