2.NBT.B: Use place value understanding and properties of operations to add and subtract.
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Second grade students need to be able to fluently add and subtract within 100. This means that you need to use mental math, and not a pen and paper, to add and subtract numbers up to 100. Second graders should be able to add up to four-digit numbers using understanding of place value and the properties of operations. Click on the links below to practice adding and subtracting larger numbers!
This subtraction poem is helpful for remembering when to regroup! Subtraction of two-digit numbers often requires you to regroup, and to be able to fluently add and subtract within 100, students need to be able to do this math mentally!
For Students!
Click here to use Xtra Math! This website is great to practice your addition and subtraction facts up to 100. To use Xtra Math, you will log in using your class login. Once you login, you'll work on math problems that are perfect for your level. Your teacher will receive a report showing how well you're doing! This is a great way to build math fact fluency.
For Teachers!
Click here to access The Educator, a newsletter published by the Lee Pesky Learning Center in Idaho. This newsletter, published in Winter 2010, outlines a study on developing math fact fluency. This article offers great suggestions for developing students' knowledge of math facts by changing your daily instruction.