Grade 1 - Number
Standard 1.N.9 - Practice solving subtraction sentences to make a specific number.
Included Skills: Subtraction, Number Properties
Describe and use mental mathematics strategies for basic addition facts and related subtraction facts to 18. • Achievement Indicators: - 1N9.1 Use and describe a mental mathematics strategy for determining a given sum. - 1N9.2 Use and describe a mental mathematics strategy for determining a given difference. - 1N9.3 Use and describe mental mathematics strategies, such as: • counting on and counting back • making 10 • using doubles • thinking addition for subtraction. - 1N9.4 Refine mental mathematics strategies to increase their efficiency.