Missing Number

Day 1:

1. Students will begin the lesson on the carpet. The teacher will explain to students that they will be adding numbers to 20.
2. The teacher will play addition video on the smartboard. After going through the problems on the video with the students, the teacher will take the time to break down the problems to ask them what would happen if they had a ‘missing number.’ (For example, the first equation in the video was 5+6=11. You would ask students 5+_=11 and have students solve the problem together.) The teacher should do this for multiple examples.
3. After watching the video, and going through examples to find the missing number, the teacher will pull out cubes and do more examples with the class using the cubes to represent the numbers. After a couple of examples, the students will break into partners and practice giving each other missing number equations using the cubes. (Give students 10-15 minutes to do this).
4. After the students have practiced using the cubes with their partners, the teacher will send students back to their tables to complete a worksheet. Students will have 15-20 minutes to complete the worksheet.

Day 2:

1. The teacher will review with students what they did the previous day with finding the missing number in an addition equation. The teacher will see if students have any questions before moving on to subtraction.
2. The teacher will place examples of subtraction problems on the board to work out with students as a class. Then, the teacher will bring out the cubes and demonstrate more examples with the students as a whole before breaking them off into partners to practice.
3. Students will break into partners and do the same thing they did the previous day, except they will be creating subtraction equations and finding the missing number. (Give students 10-15 minutes to do this)
4. After the students have practiced using the cubes with their partners, the teacher will send students back to their tables to complete a worksheet. Students will have 15-20 minutes to complete the worksheet.

Differentiation: Pull small groups for remediation as necessary. Link to background knowledge of adding numbers to 10. Build to increased numbers up to 20. Use tens frames to support if necessary.

Extension: Increase the values to thirty. Have students show the equations in multiple ways. Ex 11 + __ = 20 could also be written as 20 - 11 = ? or ___ + 11 = 20.

Students will be assessed through how they respond to examples worked out as a class. The teacher should also go around and take notes during the time they are working with partners. The worksheets will be taken up and used for an assessment also.