I have a large worm bin at my house, but I wanted to make a bin that I can keep safely at school, under my desk. This would also work underneath a kitchen sink or another small space.
My worms are mostly eating coffee grounds and shredded paper, but they also get some leftover vegetables from lunch and from home.
I used two smaller bins that fit under my desk.
After drilling holes for aeration, I covered the boxes with paper (to keep the worms in the dark), added food, soil and dampened paper for the worms to dig in, and put the boxes together.

clear boxes need to be covered

adding in organic matter after it is chopped up

I use a Keurig at work. This kind is easier to add the grounds and filters to the worm bin.

But with scissors and a little effort it is possible to use the regular K cups.

Poke a hole, dump the grounds, and peel the filter out.

I drilled aeration holes and then covered the bin with paper. I poked holes through the paper too.

Here’s my worm bin, expertly covered in leftover scrapbooking paper.

And here’s the bin, tucked away under my desk.