Educational FDM Cube (demonstration purposes)

I was asked to help some students at a lokal shool to improove their 3D printing skills. So I printed a Hotend model and packed some of my prined parts. But I was still missing something to show many of the cool features that are possiblie with 3D Printing in one Design.So I designed this FDM Cube to demonstrate the following possibilities that are not possible with standard procedures like drilling, cutting, ….Creating internal structures (Tunnel, Magnet, M3 Nut).Creating several pieces in one Part (tiny drawer).Different Materials/ Colours in one part.Different possibilities to attach screws (Nut, Plastic. Insert is not included yet)Different possibilities to fill the cavitys (Infill is visible!)I started with some TPU Filament and asked them what they think where it will poke through. First the filament wents straight through the piece. The Second hole will direct it to the bottom. I show them that it is possible to see only through 1 of the bigger holes. They were quite surprised w