This applet, with multiple levels of difficulty, enables the student to explore the meaning of balance, a key concept in developing mathematical understanding of solving equations. First, students select to work with two to four shapes of differening weights. The chosen simulation gives the weight of one shape and allows the student to experiment to balance the virtual scale by adding shapes of unknown weights. After balancing the scale, the student must determine the unknown weight for the shape or shapes and enter the information into the simulation. The student can check the solution and, if correct, proceed to a new problem. If incorrect, the student can continue to experiment with the shapes to balance the scale or choose to see the solution and move to a new problem. Copyright 2005 Eisenhower National Clearinghouse