This brings back memories. In 4H we made pin cushions using a mason jar ring lid and a mason jar sealing lid. You took padding and glued it to the flat sealing lid and then pushed the lid 'ring' down over it, gluing it into place around the edges. The padding was thick enough that the flat sealing lid was the bottom of the pin cushion with the extra fabric we glued it over the flat sealing lid covering the bottom. We made them for our 'first' project. A nice memory!
It looked like this only with a mason jar lid for the 'ring'
example