A few years ago I was explaining a helix to my six year old. So we designed one he could play with in Solidworks (triple helix vase). He still uses it as a fidget to this day. And he likes that the design details were his decisions.

I printed it with 3 perimeters, 5 bottom, 0 top, zero infill.

STL, Solidworks, Step, and Fusion360 file versions included.