For those looking for science materials, check your state Geological Survey agency for cheap/free field trip guidebooks exploring the local geology of your area.

I live in Illinois and the ISGS has, for about half a century, published field trip guidebooks for use by students all over the state, organized by locale and put the majority of them online in pdf format. You can also order hard-copies from them for a few dollars, or print them yourself from the pdf. Just scroll through the list until you find your locale:

Full List in pdf

I figure that most states may have a similar program to Illinois' so check yours, but your mileage may vary because while I'm pretty sure all US state GS's have made field trip guidebooks, not all of them make them available online.

For instance, I know that neighboring Missouri does not have their guidebooks online like Illinois (they still have a decent educational site: https://dnr.mo.gov/geology/ ) however a non-profit organization of geologists has published several field trip guidebooks from the Missouri GS for locales around the state: http://missourigeologists.org/FieldtripsandGuidebooks.htm

Another suggestion is that local libraries may carry hard copies of these guidebooks in their stacks, so if you have no luck online you can try that. If you live near a university you can try looking up the geology department and emailing them, in my experience they are always happy to help.

Like I said though, your mileage may vary depending on what state you're in but if you can find these they are great, all of the Illinois ones include supplemental materials explaining the geological concepts and structures being explored on the trip, including stratigraphic columns specific to that locale as well as a general geological history of the region/state as a whole. I'm sure other states' guides are similarly packed with good learning materials.

Anyway, just found this sub and figured I could make a small contribution. This stuff is really good for high school students, but really you can take kids of just about any age on these field trips. I've adapted it to my grade school kids easily as just visiting a place with cool rock formations (or even better somewhere with FOSSILS to collect) is enough to keep them engaged and interested. Also with the pandemic any opportunity to get outside is not to be missed!

Good luck and happy learning!