For early finishers? Math Workshop Adventures Create a new number each day. When kids finish their math assignments, they work on the number of the day problem. Introduce new concepts as the year progresses (multiplication.
Why I NOW Love Teaching Math: Setting up Math Rotations
Use for addition, subtraction -then discover how to set up for multiplication Math Facts Baseball - Practice addition and subtraction facts! There's a great statistics lesson in here too. This would really be a great project for any elementary grade.