Not a mom, so take these suggestions with a grain of salt.
Can you garden? Flowers, vegetables, herbs.
They can relate into other areas, if you're looking to maybe sell something as well. Besides food or herb satchels, you can press or dry flowers for decoration or scrap-booking, and there's a retired grandmother down the street from me who uses her little yard to grow all different types of irises and sell their bulbs in the spring. Of course, she doesn't have to deal with kids getting to them.
Can you keep pets? I remember as a kid we lived in the country, my mom did woodworking, had a little shop, and bred fancy pigeons for the fair.
You could always start smaller, breeding guppies or something?
Or not breeding at all - a pet just might make you feel better when your down; I know petting my cat always helps me.
What about artwork?
Have you ever heard of ATCs? It stands for "Artist Trading Cards", and you don't have to really be an artist. You don't even have to paint or draw - it can be sewing or collages or anything really, just so long as it ends up being around the size of a card (2.5 by 3.5 inches).
You make them, then trade them - either in person or trade them through the mail. There's forums dedicated to it
Collecting counts as a hobby, and you get the added bonus of making things other people will appreciate and "ooh" and "aah" over!
Kids can also participate and get cards made by other kids!
You can also try selling the cards you make. On ebay or etsy.