Here is another educational robot that can be 3D printed. The MiKoBots is a 3D printable robotic arm with open source software that can be used to teach kids coding and electronics. It lets you connect multiple end effector tools, including a magnet and vacuum tool. This robot has max payload capacity of 1.5kg. It weighs only 9kg, so you can easily move it around.
This robot has Bluetooth and USB connectivity. Its control software will be open source. The MiKoBots Studio has various convenient features, including simulation, Gcode interpreter, and vision control. It works with Xbox controllers. This project is going to be on Kickstarter soon.