These files are contain minbus 2d data (dxf) and 3d data(stl) that will allow you to manufacture using 8mm thick wooden plate. If you want, you can paint and use without wheels and wheels. it will be fun and educational for your children. have fun.
STL (Stereolithography, filesize: 908 KB), DXF (DXF, filesize: 305 KB), BLEND (Blender, filesize: 727 KB)