## ◂Math Worksheets and Study Guides First Grade. Subtraction Facts

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

#### Maryland College and Career-Ready Standards

MD.MA.1.OA. Operations and Algebraic Thinking (OA)
1.OA.A. Represent and solve problems involving addition and subtraction.
1.OA.A.1. Major Standard: Use addition and subtraction within 20 to solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem.
1.OA.A.1.1. Ability to represent the problem in multiple ways including drawings and or objects/manipulatives (e.g., counters, unifix cubes, Digi-Blocks, number lines, and part-part-whole mats).
1.OA.A.1.2. Ability to take apart and combine numbers in a wide variety of ways.
1.OA.B. Understand and apply properties of operations and relationship between addition and subtraction.
1.OA.B.4. Major Standard: Understand subtraction as an unknown-addend problem. For example, subtract 10–8 by finding the number that makes 10 when added to 8.
1.OA.B.4.2. Ability to apply the strategy to think addition rather than take away: Rather than find 9-6 = ?, ask how many would you add to six to equal nine?
1.OA.C. Add and subtract within 20.
1.OA.C.5. Major Standard: Relate counting to addition and subtraction (e.g., by counting on 2 to add 2).
1.OA.C.5.2. Knowledge of and ability to use subtraction counting strategies (Counting Up To, Counting Back From) to solve problems.
1.OA.C.6. Major Standard: Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on, making ten (e.g. 8+6 = 8+2+4, which leads to 10+4 = 14); decomposing a number leading to a ten (13–4 = 13–3–1, which leads to 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, which equals 13).
1.OA.C.6.1. Ability to use mental math strategies such as counting on, making ten, decomposing a number leading to ten, the relationship between addition and subtraction, and creating equivalent but easier or know sums to add and subtract within 20, first using visual models and then moving to mental math.
1.OA.C.6.2. Ability to demonstrate fluency for addition and subtraction within 10, building first on accurate recall of the facts using games, (including technology) and purposeful practice (Tasks which are timed should not be used unless students have demonstrated accurate recall of the facts).
1.OA.D. Work with addition and subtraction equations.
1.OA.D.8. Major Standard: Determine the unknown whole number in an addition or subtraction equation relating three whole numbers. For example, determine the unknown number that makes the question true in each of the equations: 8+? = 11, 5 = ?-3, 6+6 = ?.
1.OA.D.8.1. Ability to represent the problem in multiple ways including drawings and or objects/manipulatives (e.g., counters, connecting cubes, Digi-Blocks, number lines).
1.OA.D.8.2. Ability to take apart and combine numbers in a wide variety of ways.
MD.MA.1.NBT. Number and Operations in Base Ten (NBT)
1.NBT.C. Use place value understanding and properties of operations to add and subtract.
1.NBT.C.4. Major Standard: Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, 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. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones, and sometimes it is necessary to compose a ten.
1.NBT.C.4.2. Ability to model addition and subtraction using base ten manipulatives (e.g., base ten blocks, Digi-Blocks, Unifix cubes) and explain the process.
1.NBT.C.6. Major Standard: Subtract multiples of 10 in the range of 10-90 from multiples of 10 in the range of 10-90 (positive or zero differences), 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.
1.NBT.C.6.3. Ability to model subtraction using base ten manipulatives (e.g., base ten blocks, Digi-Blocks, Unifix cubes) and explain the process.