We have developed new rotors that can be classified into three groups by changing the rotors used in simple motors into various types. Group I has a semicircular shape rather than a perfect circle or square shape, group II has a structure consisting of several closed circles on one plane, and group III has a three-dimensional shape. We wanted to show students that a closed circular shape is not the only thing that can rotate in a magnetic field, and that various types of rotors are possible. Also, we think it would be good to give students an opportunity to envision different shapes of rotors.