Students can play in pairs (1 vs 1) or groups of 4 (2 vs. 2). Each person or team has a hockey net. A hockey stick problem card is flipped over. Each card has a fraction that is equal to a percent. Students have to estimate the missing number (For example, 8 out of 21 equals ____%) Each team estimates what percent 8/21 equals without a calculator. Then, the problem is put in a calculator. Whoever is closest to the actual answer “scores a goal” and puts a puck in their opponent’s net. There are also cards where the fraction is missing a numerator or denominator and it says what percent the fraction equals. (For example, ?/60 = 40%. Students work to figure out the best estimate for what number out of 60 would make 40%.) Whoever has the most pucks in their opponent’s net in the end is the winner.