The incident happened on Monday morning near 67th Avenue & Lower Buckeye.
Police say the man engaged the girl in a brief conversation then grabbed her backpack and pushed the girl to the ground. He reportedly fled when she kicked him and called for help.
The suspect is described as a black male, 20-30 years old, thin build with a mustache and beard. He was seen wearing blue jeans, a blue hoodie, and tennis shoes.
Anyone with information on this crime is asked to call Phoenix Police or Silent Witness at 480-WITNESS.