Squish the class to the back of the room. Instructor assigns a simple combination that is performed down the room. At other end, the senior student adds another technique to the end of the combination. Perform the new combination down the room. Then the next highest rank adds another, etc. etc. Sometimes start with the lowest rank and work upward.
Put students into sitting horse stance. Point to the direction you want them to go, using the 4 basic directions. The students have to jump, turn, and land in their horse stance to face that direction with three quick punches, blocks, etc.
Have each student each call out a stance and a technique. All students do the stance and perform the technique 10 times.
Have class double time while in a single line. Last person in the line sprints to the front. The line gradually shifts backward to accommodate the person and then the next (rear) person will do the same etc. Once everyone in the line has sprinted, the "run" is finished.
Performed the same way as traditional tag, but with a few twists. Students must keep moving at all times, any student that stops moving is out. When you tag someone, you must yell "Taekwondo" or the tag does not count