Addition and Subtraction Number Ladders
Mrs. Bohaty's Kindergarten Kingdom: Math tools
Rowdy in First Grade: My Guided Math
Simple idea but I bet it would be an effective reminder
5 Games to Play With a Hundreds Chart (Free)
Math Coachs Corner: Problem Solving...Let Them Struggle! Japanese teachers typically allow students to struggle the most with problems. Teachers in Germany stepped in to help a little quicker than the teachers in Japan. In the United States, however, teachers typically offered assistance at the first sign of struggle or frustration.
Math Coach's Corner: Problem Solving...Let Them Struggle!
Representing Numbers Foldable - great when studying place value.
Missing Addend Freebie