This is an AMAZING-- I may even go so far as to say MIRACULOUS-- activity! It turns a worksheet into an activity that encourages collaboration and problem-solving, while strengthening their knowledge of this unit.
Assign your students to partners. Each student works out their problem #1 on their own paper. When they finish, partners compare answers. Even though they are completing different problems, they should both get identical answers! If their answers do not match, they should look over each other’s work to find the mistake. This tremendously strengthens their algebra skills! When they agree upon an answer, they should move to the next problem and continue this pattern until they complete the entire column. I then assign the other column to them as homework so that everyone completes every problem on the paper. This also allows students to know all of the correct answers in advance when they are doing their homework so they will be 100% certain that they are correct.