Subtraction Within 20

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1st Grade Subtraction Within 20 GameFirst Grade Subtracting Numbers up to Twenty Game

Math Practice Lesson - Subtraction within 20

Are you ready to practice basic subtraction within twenty? This lesson will help your students become subtraction experts! All subtraction problems in this basic math lesson have minuends and subtrahends less than 20. To find the difference, students will be presented with a variety of question types.

Some problems feature a set of counters. Some of the counters have X's through them to represent the part that is taken away, or the subtrahend. The counters are accompanied by a subtraction number sentence. Other problems are word problems. Here's an example of a subtraction word problem your students might be given: 'Emily made 12 snowballs. 3 melted. How many does she have now?' Still other problems might be presented as word problems accompanied by a number line, such as: 'What subtraction sentence does the number line show?' Students will either type their answer in the blank space or choose from multiple choices.

1st Grade Subtraction Within 20 LessonFirst Grade Subtracting Numbers up to Twenty Lesson

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Try out this subtraction within twenty lesson today! We hope you like it! Make sure you also browse our complete collection of other math topics too!

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When students log in with their own user name and password, they will see a student version of the site homepage complete with large icons and a kid-friendly layout. Under the 'My Assignments' section, they'll be able to see what math lessons were given to them by you. They will also be able to explore additional topics and lessons at their grade level, or even math lessons at other grade levels, should you choose to make that option available to them under your account settings. Grade levels in student mode appear as 'Level A,' or 'Level B' instead of 'Grade 1' or 'Grade 2'. This way, you can assign lessons based on your students' skill level.

1st Grade Subtraction Within 20 ActivityFirst Grade Subtracting Numbers up to Twenty Activity


This interactive math lesson is considered a Level A lesson. It may be ideal for first grade students.

Common Core Standard

1.OA.1, MA.1.NSO.2.2, 1.3D
Operations And Algebraic Thinking

Represent And Solve Problems Involving Addition And Subtraction.
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.2

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Subtraction Fact Drills within Ten (Level A)
In this first grade-level math lesson, students will practice subtracting within ten. Questions are presented in a drill-style format.

Subtraction Fact Drills within Twenty (Level A)
Students will practice subtracting within twenty in this first grade-level math lesson. Questions are presented in a drill-style format.