Here is another cute STEM robot kit for kids. The Jimu Robot BuilderBots Kit has interactive building blocks that can be used to make GrabberBot and DigBot robots. It comes with 4 servo motors, infrared sensor, LED light, main control box, and a total of 357 parts and connectors.
The companion app is available for iOS and Android devices. It has 3D building instructions. pre-programmed actions with Blockly coding, and a joystick remote to control the robot from your smartphone or tablet.