Addition and Subtraction Story Problems

1. Students will begin the lesson on the carpet. To begin the lesson, the teacher will flash a number, 1-20, to students and have the students say the number quickly. The teacher could also have the students count up to 20 and back starting at 20.
2. Start by giving a subtraction word problem to students to solve. They should solve using their whiteboard and markers while the problem is displayed on the smartboard. Give students 5-6 minutes to work on the problem on their own, then give students 1-2 minutes to discuss with a partner. After this, then the teacher will work the problem out for students and also share one or two students' work and how they solved it. (Try to pick students who took a different approach to the problem to show that there is more than one way to solve it.

Story Problem Example: There were 8 children in the park. 4 of the children were wearing blue shoes. The rest of the children were wearing black shoes. How many children were wearing black shoes? Please solve using a number sentence, number bond, and a written response.
 
3. After going over this with students, walk students through on how to turn the subtraction number sentence in the problem into an addition sentence. 8-4=4 to 4+4=8.

4. Have students erase their boards and do another problem exactly like the one above. 
Story Problem Example: There were 9 butterflies on a bush of flowers. 5 of the butterflies were blue and the rest were pink. How many butterflies were pink? Please solve using a number sentence, number bond, and a written response.
 
5. Have students change the number sentence into an addition sentence on their own this time before showing them the correct answer.

6. Send students off to do the worksheet. (the worksheet could easily be done in a small group, or more problems like the ones above could be done in smaller groups depending on student’s abilities.) Give students about 15-20 minutes to do the worksheet.

7. Go over the worksheet with students, having them share out answers, and how they were able to solve the problems.

Differentiation: Activate prior knowledge with number bonds. Give a completed example and create a number bond. Pull in small groups and remediate as necessary.

Extension: Increase the number of addends to 3. Provide students with an equation and have them create a word problem/scenario to accompany. 

Students will be assessed through the mini lesson that is done and if they are able to solve the problems correctly. Students will also be assessed on the worksheet given, and during the share portion of the lesson.