Before I give you any advise allow me to give you my resume/CV. I current work in a game store, and I sold on Ebay professionally for a few years. I bought collections and moved them on Ebay, consigment cases, and local cons. So I know abit about this. Depending on the money you want to get, you have several options. While you say you don't want to get rich, there is a difference between market pricing, less than market pricing, and fire sale pricing. Since you are looking to turn the money around and use it to teach kids, I think it may worth the effort to get market prices for them. You will need to find the manufacturer(s). After that, do a search on ebay for similar figures and be sure to check the "sold" box on the menus to the left. This will show you what they have actually sold for, and give you an idea of their value. This research will take a couple of hours, but will ensure you get the most back for your classes. Next up is choosing a venue for selling.
Ebay is the most reliable, as it is always there, sells to most of the world, and is easy to sell on. A downside is the 15-20% commission they charge. But once you get set up and have photos, you can see a return in a week! Be careful about putting too much up at once. Having to pack up more than 20 packages in a day is work. Additionally try not to put up too many of the same item. 5 auctions of "Napoleonic French Grenadiers" will drive down the price on all of them, but selling 1 a week for 5 weeks will get you a much better return.
Gaming stores often have consignment cases, where you can place figures, the store will sell them, and give you either money, store credit or both. Some charge a percentage if you want cash, though if you use the money to buy paints and supplies through them you should get 100% in store credit. The biggest down side is the limited number of customers who will see them, which means it will take longer to sell them. Also in my experience, customers want a better deal in consignment cases. Otherwise they could just buy them on Ebay! Another potential option is to run an auction. I am assuming you inherited this upon your friends death (my condolences for your loss). If you and your friend were regulars at a gaming store, you could work the owner to run either a memorial auction or flea market table(s). This would both you and the local community a chance to remember your friend. The figures would also get used locally, giving local players another reason to remember him. Hedk, you could even set up gaming days were the buyers could bring the figures back and fight battles with them. This could even be turned into a charity event, with playes donating money, buying dice rerolls, etc., and the proceeds going to a favorite charity of your friend. With a little work, this could be a yearly event. I have a friend whose wife runs a yearly Warhammer 40K "Battle for the Boobies" in my store, in memory of her mother who passed from breast cancer. Last time we raised over $1400!
Conventions often have flea markets. They charge a small fee, but no commision. Being in PA, I am sure you are aware of the big cons there. A flea market table at Historicon would net you a large number of customers, with large amounts of cash in their pockets. I have found that convention customers also want a deal, but you could potentially sell the entire collection in a day, sometimes in a few hours! And you have an excuse to attend the con!
You can also sell them here. While not as convenient as Ebay (you will have to do a little more work) there is no commission. And while we are a mighty and vast breed here, it is not as big a customer base as Ebay. That said, I have yet to buy anything from this forum, as by the time I look at a post for selling, everything is gone already! (Stupid west coast time differential!) I have seen entire collections go in a day, usually less than a week. And after you post pics, and we all figure out what you have, you should already have customers!
If you have any questions please ask!