In this activity, students examine cards with 4 equations. The equations have missing information and, in some, the sum or difference is listed to the left of the equal sign. (For example: 7 = 3 + __ ) Students need to identify the equation that is not related to the other three. Related facts with sums up to twenty are included in this activity. Students record the letter of the equation that is not related to the other three.
There are 2 sets of 20 cards included in this product for a total of 40 oddball cards. Answer keys are included.