Arduino is a wonderful platform for learning coding. The Yahboom Mecanum Coding Robot comes with everything you need to build a smart omnidirectional robot. It has a HD camera and can connect to iOS and Android devices. It also features 5 infrared obstacle avoidance sensors.
The Yahboom Mecanum Robot for Arduino UNO R3 has 3 sports modes. It ships with motors, 4 wheels, main control board, and the other parts you need to put it together. Costs under $110 at this time.