I sprayed a blob on each student's desk and had them create an area to work out their math problems. I then gave them a 2 digit by 1 digit multiplication problem for them to practice their partial product and standard algorithm method.
They had an absolute blast. I didn't have much shaving cream to go around, so we only did this activity for about 15 minutes. I told the kids if they brought more shaving cream that we would do it again. I had two more cans the next day. It basically created a white board for them to write on with their fingers instead of an expo marker. When they are finished their is no clean up other than telling them to completely rub the shaving cream into their desk. You should definitely try it sometime you could use it for infinite possibilities.