Write "Happy 100th Day" on the whiteboard. Underneath, write 13 fitness activities (or any random number that cannot be evenly divided into 100.) Some examples are: ski jumps, crab kicks, running steps in place, crunches, reverse push-ups, etc.

Write the following rules:
1. The challenge is to do at least one repetition of each exercise so that the grand total equals 100.

2. All team members must do all of the exercises together at the same time and count.

3. You must show your work (the addition problem on your paper.)

4. You may abbreviate the names of the exercises such as s.j. for ski jumps.

5. When you are finished with the exercises your team must also write one fact you have learned in the last 100 days in physical education class and hand your paper to the teacher.

Divide the class into groups, approximately 3 students per group. Give the students 2-3 minutes to strategize or brainstorm how they will reach the total of 100. Encourage them to listen to everyone's ideas. When everyone is ready to start, play some music. As groups finish, have another activity for them to do, such as jump rope skills. That way everyone stays active until the whole class gets done.

After all of the groups are finished, have the whole class sit down and talk about their strategies. It is quite interesting to hear how they decided to have their sum equal 100. After hearing the others' strategies, ask if any of them would change their strategy and why.