Some drag-and-drop math games are educational for kids. "Drag and Drop Math" on MrNussbaum.com teaches addition, subtraction, multiplication and division; the game is suitable for ages 6 to 12.
Math-Play.com offers the educational drag-and-drop game "Classifying Triangles" in which the student must drag and drop each triangle into the correct category as quickly as possible. "Adding Integers" is another educational game in which the player is given sums with positive and negative numbers, and must place them in the correct categories according to whether their answers are positive, negative or zero.
FunBrain.com also offers "Bumble Numbers." In this game the player must collect flying numbers and drop them into flowers containing sums to which they are equal.