This 39-page packet analyzes the second grade common core math standard 2.NBT.5 (Use place value understanding and properties of operations to add and subtract; Fluently add and subtract within 100, using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction).
18 Lessons on Addition to 100 (Using Place Value, Number Lines, and Standard Addition)
18 Lessons on Subtraction to 100 (Using Place Value, Number Lines, and Standard Subtraction)
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