As a homeschool family, we have undertaken many interesting projects. We have mummified a chicken (thank you Story of the World), dissected frogs, and raised butterflies.
Requirement #11 of Insect-a Inspect-a requires the girl to raise butterflies from caterpillars. If you are looking to complete this requirement. There are a couple of sources for live caterpillars. Amazon does sell kits that include a voucher for caterpillars. I used Insect Lore (here) a few years back when my daughter completed this requirement.
This is not an affiliate link, and I do not receive compensation from them. I am only sharing the resources I have found that may be helpful to you.
If you are looking to complete the Insect-a Inspect-a badge, check out these resources:
NOTE: The requirements have been simplified here. Please be sure to read the full text in the American Heritage Girl Handbook to make sure you fully understand the requirements.