Here is a desktop submarine pencil case broken down into three printable parts. I also smoothed out the curves on the ends from the original one I made. The screw (propeller) comes out to fit pencils into the hollow sub, and the sail (top part of the sub) also has room in it for an eraser. 12 holes in the front of the sub can fit pens or pencils as if they were cruise missiles launching.
Please leave a comment if you like it.
This thing was made with Tinkercad. Edit it online tinkercad.com/things/dT7PrcAkt3O