I'm convinced that whoever is doing the work in the classroom is the one doing the learning. This means I try to minimize the time I spend doing dramatic performances of math problems, and maximize the time the students are working. My goal for every lesson is to expect the class to sit and listen to me for less than 20 minutes, leaving at least 25 minutes for them to work.
So we face a situation at odds with itself: kids need to practice doing math problems, but sitting and doing math problems is boring. To resolve the situation, I have collected an arsenal of structures that are a step up. Logarithm Wars is an example. Solve-Crumple-Toss came from a colleague, who is a master at thinking of these structures (thanks, Jen).
You need 6-8 problems that have somewhat lengthy solutions, not quick ones. Today I used this for proving and solving trig equations. Each problem gets its own 1/2 sheet of paper. Make copies and chop them in half. I usually allow 3-4 problems per student.
To kick things off, pass out 1 problem per student, and place the remaining problems where students can easily pick them up. When they have completed a problem, they bring it to you for checking. If there are errors, you give them some hints and send them back to their seat to fix it. If it's correct, the student crumples the paper, stands behind a line on the floor, and throws it at the garbage can for a bonus point. I actually use two targets: the recycling bin for 1 point, and the garbage can (which is smaller, and farther away) for 2 points.
It works pretty well. The athletic kids get to show off their skills, it requires students to get up and move around a little, and there's an incentive for getting a few done, and done correctly.
If you are lucky, you will have a student ask if they can get a running start and take off from the line. This can be very entertaining, and I love having my Flip for these moments: