Eai Education Math Stacks Geometry Game: Grades 6-8The cards are stacked in everyone's favor with Math Stacks! Students take turns drawing match cards and using mental math look for the equivalent starter card on which to stack it. Once a three card stack is made it can be collected. The person with the most stacks at the end of play wins! Differentiate the level of play by removing unwanted Math Stacks starter cards and their matches. Each Math Stacks game contains a total of 60 cards. The Geometry