I'm Thinking of a Number is a game designed to build reasoning, basic fact recall, vocabulary and place value understanding. It also develops mental math fluency - a skill that requires children to "hold information in their head" while processing new information. I'm Thinking of a Number has two levels for both green and orange cards which increase in difficulty. Each set has 20 cards with step-by-step instructions on how to solve the problems mentally. Additionally, a vocabulary "cheat sheet" is provided for additional support.