This activity is basically a race. Split the class into two teams and have one team member from each team come up

This will be your students in no time!

to the board to work a problem. Put the problems in a PowerPoint so that the people racing can see it clearly and the rest of the class can as well. Then, have everyone work the problem. The team member at the board who gets the answer correct first earns a point for their team. If a person at the board does not know the correct answer, someone else from his/her team can try at the board. Then, go through each step and clarify any questions. Display the answers to each problem on the PowerPoint and make sure everyone has the correct answers. This works best when people are comfortable with the material but can also challenge those who need more practice. 

Bring candy for the winning team, if you can. Send out the PowerPoint with practice problems and answers to everyone who attended after to use as a study tool.

From Baylor University