The development for improving research material is arranged to improve the susceptibility of children, passes through overlapping or the adjacent circle with different sizes. The development for improving research material includes one first element (100), a second element (110) and third part. First element includes the file of dyeing with different sizes and shapes. Second element includes the Colored Paper with various sizes of hole. Attached drawing is drawn in third part. Third part is translucent. The side of first element is cut to selected shape.
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