Math Games

Grade 2 - Number

Standard 2.N.9 - Complete the addition sentence by filling in the missing number with sums up to 100.

Included Skills:

Demonstrate an understanding of addition (limited to one- and two-digit numerals) with answers to 100 and the corresponding subtraction by:
• using personal strategies for adding and subtracting with and without the support of manipulatives
• creating and solving problems that involve addition and subtraction
• explaining that the order in which numbers are added does not affect the sum (commutative property)
• explaining that the order in which numbers are subtracted may affect the difference.

• Achievement Indicators:
- 2N9.1 Model addition and subtraction, using concrete materials or visual representations, and record the process symbolically.
- 2N9.2 Solve a given problem, using horizontal and vertical forms.
- 2N9.3 Add a given set of numbers in two different ways, and explain why the sum is the same; e.g., 2 + 5 + 3 + 8 = (2 + 3) + 5 + 8 or 5 + 3 + (8 + 2).
- 2N9.4 Create an addition or a subtraction number sentence and a story problem for a given solution.
- 2N9.5 Solve a given problem involving a missing addend, and describe the strategy used.
- 2N9.6 Match a number sentence to a given missing addend problem.
- 2N9.7 Solve a given problem involving a missing minuend or subtrahend, and describe the strategy used.
- 2N9.8 Match a number sentence to a given missing subtrahend or minuend problem.
- 2N9.9 Refine personal strategies to increase their efficiency.