## ◂Math Worksheets and Study Guides First Grade. One Less, One More

### The resources above correspond to the standards listed below:

#### Kansas Academic Standards

KS.1.OA. Operations and Algebraic Thinking
Understand and apply properties of operations and the relationship between addition and subtraction.
1.OA.4. example, subtract 10−8 by finding the number that makes 10 when added to 8.
Add and subtract within 20.
1.OA.6. Add and subtract within 20, demonstrating fluency (efficiently, accurately, and flexibly) for addition and subtraction within 10. Use mental strategies such as counting on; making ten (e.g. 8+6=8+2+4=10+4=14); decomposing a number leading to a ten (e.g. 13−4=13−3−1=10−1=9); using the relationship between addition and subtraction (e.g. knowing that 8+4=12, one knows 12−8=4); and creating equivalent but easier or known sums (e.g. adding 6+7 by creating the known equivalent 6+6+1=12+1=13).
KS.1.NBT. Number and Operations in Base Ten
Extend the counting sequence.
1.NBT.1. Count to 120 (recognizing growth and repeating patterns), starting at any number less than 120. In this range, read and write numerals and represent a number of objects with a written numeral.
Use place value understanding and properties of operations to add and subtract.
1.NBT.4. Add within 100 using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used including:
1.NBT.4a. Adding a two-digit number and a one-digit number.