OMG! I came across a math blogger, Sarah Carte @math=love.blogspot.com, who used question stacks. These are so cool. The template is set up with questions and answers on the back. The back of the card is not the answer to the question. Students put all answer cards facing up and then turn one over to reveal the first question The student answers the question and find that answer on one of the answer cards. They take the answer card place it on top of the question (answer side down) and the next question is on top. You continue doing this until all the cards are used up. The student knows they did the stack correctly if the answer to the last question was the first card placed on the bottom. So fun. I created a stack for my energy unit.