I ordered a butterfly hatching kit for the boys and since there were some other August birthdays last month, I order a few kits and gave them away as presents. The kit that I kept had five small caterpillars that are inside a clear plastic container. They have food on the bottom of the container and they live their whole larval stage inside the container. The boys loved to watch them and everyday they seem to double their size. Then after a week and a half, they hang from the top of the lid and make J shapes and then start building their chrysalids. We had one caterpillar that took almost four or five days after the others turned to form a chrysalis and we thought he was a goner. We placed the lid with the chrysalids into the butterfly net and after a week, they slowly emerged as butterflies even the slowpoke guy. We kept them in the net and fed them watermelon pieces and tissues dipped in sugar water.
After three days, we decided to release them. Some flew out quickly but some had to be coaxed out.
It was very easy and a lot of fun. If you are thinking of doing this, I highly recommend getting the butterflies and net through Insectlore. They have a deal where you get the caterpillars and the net for $20 and 3 out of the 5 caterpillars are guaranteed to turn into butterflies. They have great customer service, their products are excellent, and the packing peanuts turn to mush if you put it in water which is good for the environment.