This is a super cute idea! You can do this project with children because this is not only a handcraft, but also a scientific experiment!
What you need:
First draw the silhouettes of butterflies over a piece of paper and cut them. Then measure the paper around the jar and cut it. Turn it to a cylinder and glue butterflies to it. Then make a curved shape from one end of the wire and attach butterflies to it with a thread. Wind it around the mouth of the jar. Glue the cylindrical paper with butterflies to the jar. Put in a candle and your lantern is ready. wow~~Butterflies dancing now!! I think you know why, right? Happy crafting!