Send a letter - modern youth associates this action only with e-mail. But sometimes you have to send paper letters, but you need an envelope for them. In the era of electronics, such a trifle is not found in every home, so you have to think how to make an envelope out of paper with your own hands. Like and small wisdom, but without the ability to cope with such a task.
Paper airplanes are easily made, and most importantly - they really fly. This process is so interesting that any adult will be happy to make light paper structures and, to the joy of the children, send them flying. Well, older children themselves will be able to do aircraft design.