A design for a circular, piece-matching math educational aid is disclosed. It contains a holding plate and various fraction pieces. The circular holding plate has a clockwise spiral bottom, designed in such a way that a sloped cliff is formed at the joint of the starting and ending point. The edge of the cliff is lined up with a guiding mark "0" on a fraction scale marked on an elevated wall on the outer circumference of the holding plate. The fraction pieces contain numerous pie-shaped segments. Any of the segments can precisely depict a fraction, based on the ratio of its center angle to the circle, 360 degrees. The pieces can be made with any center angles, such as 5, 7.5, 10, 30, 45, 60, 90, 180 degrees, etc.
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