Simple pencil tray. I designed this tray to fit on top of the Moduler Drawer Organizer (https://www.thingiverse.com/thing:3827538) on a 54 x 180mm section. This allowed me to double up pencil storage in this compartment.

I set this up as a parametrized model in FreeCAD, so you can modify the tray to fit your needs.

The lip will require supports for printing. I painted on a thin layer of supports near the edge, and that worked great. The supports were easy to remove.

I printed with 0.2mm layer height. I printed with 3 top and bottom layers, 2 perimeters, and 10% infill, and the result was plenty strong. But I don't think this will matter much as the part is mostly solid fill.