Strand: OPERATIONS AND ALGEBRAIC THINKING (1.OA)

Represent and solve problems involving addition and subtraction within 20 (Standards 1–2, 5–6). Understand and apply properties of operations and the relationship between addition and subtraction (Standards 3–4). Work with addition and subtraction equations (Standards 7–8).

Standard 1.OA.2

Solve word problems that call for addition of three whole numbers whose sum is less than or equal to 20. For example, use objects, drawings, and equations with a symbol for the unknown number to represent the problem.

• \$20 Dot Map
This problem helps students to practice adding three numbers whose sum are 20 or less. It is an open-ended problem with many solutions. This problem would work well either as a whole group or students could work on it as individuals or pairs.
• Daisies in Vases
Given a scenario about daisies and vases, students must try to find as many ways as they can to put the daisies in the vases with the most in the large vase and the least in the smallest vase. They then must explain how they know they have found all the possibilities.
• Georgia Standards of Excellence Mathematics
GeorgiaStandards.Org (GSO) is a free, public website providing information and resources necessary to help meet the educational needs of students. The goal of this web site is to provide information that will enhance and support teaching and learning of Georgia standards.
• Grade 1 Math Module 2: Intro to Place Value Through Addition and Subtraction Within 20 (EngageNY)
Module 2 serves as a bridge from students' prior work with problem solving within 10 to work within 100 as students begin to solve addition and subtraction problems involving teen numbers. Students go beyond the Level 2 strategies of counting on and counting back as they learn Level 3 strategies informally called "make ten" or "take from ten."
• IXL Game: Addition: Word problems
This game helps first graders understand addition using word problems. This is just one of many online games that supports the Utah Math core. Note: The IXL site requires subscription for unlimited use.
• Making a ten
This task is designed to help students visualize where the 10's are on a single digit addition table and explain why this is so. This knowledge can then be used to help them learn the addition table.
• Operations and Algebraic Thinking (1.OA) - First Grade Core Guide
The Utah State Board of Education (USBE) and educators around the state of Utah developed these guides for First Grade Mathematics - Operations and Algebraic Thinking (1.OA)
• The Very Hungry Caterpillar
In this math lesson the teacher reads the book to the class and asks, "How many things do you think the caterpillar ate in this story?" The students take a minute to share their estimate with a partner. Next, the teacher reads The Very Hungry Caterpillar again. After each page, the teacher pauses so that the students can add counters or unifix cubes to the ten-frame to represent the number of things the caterpillar ate, and then write an equation on the dry-erase board connecting addition to the number of counters used.

http://www.uen.org - in partnership with Utah State Board of Education (USBE) and Utah System of Higher Education (USHE).  Send questions or comments to USBE Specialist - Shannon Olson and see the Mathematics - Elementary website. For general questions about Utah's Core Standards contact the Director - Jennifer Throndsen .

These materials have been produced by and for the teachers of the State of Utah. Copies of these materials may be freely reproduced for teacher and classroom use. When distributing these materials, credit should be given to Utah State Board of Education. These materials may not be published, in whole or part, or in any other format, without the written permission of the Utah State Board of Education, 250 East 500 South, PO Box 144200, Salt Lake City, Utah 84114-4200.