I saw your question on the mathematics bookshelf, and I wanted to see if i could help out. Wikibooks in general frowns upon creating random pages full of lists, so it would be a bad idea to simply create a page that lists highschool-appropriate classes. However, there are 2 techniques that you could use, if you want to lump all such pages into a single reference source:
- you can create a subpage in your user namespace to hold the list. User namespaces are generally free from the restrictions in other parts of wikibooks, although some restrictions still apply. You can list all relevant pages on your user page namespace.
- you could create a template that would tag certain pages as being "highschool appropriate", and then create a category for that template. All the tagged pages then would appear under the category, which you could browse.