With some simple sticker-backed electronics and copper tape, anyone can create simple paper circuits to create all sorts of creative projects, including pop-up books.
When people usually think of creating circuits, they tend to think of soldering wires together on some silicon surface. This usually requires special knowledge and equipment. Plus soldering irons get hot and create fumes, which is not always accessible to children or people with allergies. This also is a barrier to learning even the most basic concepts of electronics.
Luckily a lot has changed.