Make numbers a part of your everyday routine. Your child might not like addition, but he may enjoy counting the number of stop signs on the drive to school or the number of stairs on your porch. Lead by example to encourage your child to think of math exercises as a part of his daily routine.
Divide students up into teams of 4, and number them off so each person plays the role of Team Member 1,2,3, or 4. Ask a question from the worksheet and provide 30-60 seconds for each group to agree upon an answer. They should ensure every person on the team understands the reasoning, as they won't know which team member will be responsible for answering the question. Then, randomly call out a number between 1 and 4. The person on each team whose number was called writes his or her answer on an individual dry erase board (or sheet of paper). Team members can NOT help in any way, or they will lose a point. On your signal, the designated student holds up his or her board/paper to show the answer, and you (or a student volunteer) can award and record points on the board. When time is up, the team with the most points wins.