Wanna see something HUGE...That is one of my 2 BIG 2 be true organic zucchinis I grew this year! Trust me when I say I made zucchini everything this summer - soup, bread, baked, for breakfast, for lunch, for dinner, for every meal. Zucchini is best eaten when it is younger, as the veggie grows the plant begins to go to seed and the skin toughens till it gets to a not so edible stage in it's life cycle. For collecting seeds it's good to let one (or more) of your zucchinis grow into a huge monster that would make a porn star cry (see pic above) - let it stay on the vine until the plant dies back. After I picked the obscene seeding zucchini off it's dead vine I let it sit out in the sun to 'ripen' up and harden. You can see there's a group of roving gamblers chilling out on some of mine. That's a gang of garden killers conspiring together -cute but very unnerving. ;)
Carefully open up the zucchini close to the middle but don't push your knife all the way through unless you don't mind having a few casualties. The seeds sit right in the middle, so gently pull it apart and scoop it out by hand, (just like with winter squash).
Stick them on a dish, cutting board, unbleached paper towel or some other surface for drying - be careful not to let them sit out too long and re-moisten after drying, which might cause mold. Spreading them out helps faster drying, not like I have them in the pic below. :)