My mother has baby guppies right now and they are just in the tank with the adults and a ton of plants. She figures if they make it they do, if they don't .... I am hoping because I got her red guppies that she gets some nicer ones that I can trade in at the LFS for store credit or something. But I know that's wishful thinking.
To give away some fish you can post them on here or use Craigslist, which I always have had good luck doing when I have had an excess of snails. Just be prepared to not get much money for them. If you do have really pretty ones perhaps the LFS will take them. You won't know until you ask.
I agree, it is a lot of fun watching them grow up and its a good experience, especially if you decide to try your hand with other fish down the road. Good luck!