I collected seeds from several pumpkins this past October. I'll have a "give away" for most of the seeds, but first, I need to know what type of pumpkins they are! The pumpkins were acquired from several sources, some from grocery stores and some from plant nurseries. Please ID!
There is a good chance you may have a hybrid pumpkin from the grocery store. Its seeds will give you a wide range of plants. If you grew multiple varieties of the same species, you will have hybrid seeds in your pumpkins. Again you will get a mix of plants next year.
If you really want to collect seed from multiple varieties of the same species, you need to learn when a female flower is going to open the next day. Once you learn that, you need to tape that flower shut at night so it won't open and get pollenated by bees. You need to go out in the early AM and take a male flower and brush its pollen on the female flower and then bag the female flower to exclude bees and mark it so you will know that fruit has the pure seed. You have to let that fruit get fully mature before harvesting.
Cucurbita pepo is zucchini, patty pan, acorn as well as a lot of pumpkins.