Lesson objective: Solve 2-step story problems that involve addition and/or subtraction using a number line.
This lesson provides an opportunity for students to apply their knowledge and understanding of modeling addition and subtraction problems on a number line diagram to a real-life situation. Students are asked to write equations and draw number line diagrams to solve a problem with a multi-step solution.
Key Concept students will use:
- We can use a number line to solve many types of addition and subtraction problems.
Skills students will use:
- create an addition or subtraction equation with an unknown to represent a problem situation (Grade 1, Unit 18)
- model addition and subtraction using a number line diagram
Students engage in Mathematical Practice 7 (Look for and make use of structure) as they look for number patterns and relationships on the number line to develop computational strategies.
Key vocabulary:
- addend
- compare
- number line diagram
- unknown
Special materials needed:
- blank number line diagrams (optional)
