Bit of a random one, but for those have little kids, this was great.
https://www.insectlore.co.uk/butterf...erpillars.html

We sent off for the caterpillers which came in about 5 days. Set it up about a week an half ago. Released the butterflies today.

My daughter got it for her 5th birthday. She loved watching these tiny catepillars grow everyday, then turn into chrysalises and finally hatch.
You get everything you need in terms of a net and food. To be honest I got quite invested in it as well.

Out of the 5 caterpillars, 4 survived.