Come try my activity before buying it!What's this?20 Boom cards in which students must: 1. Find the missing addend. 2. Select the correct number from 3 choices. DescriptionHere are 20 task cards to practice the missing addend in additions and subtractions whose result is equal to or less than 20. It is a self-correcting activity with which the child receives immediate feedback. It can be used in a math center, in a large group, at home, in a learning and recovery context. in class. How to access