Thanks to Lisa Louise Cooke for her helpful article "Top 10 Strategies for Finding School Records for Genealogy." It is published in her blog: Genealogy Gems.
The article is filled with examples and photos that help make the presentation easy to follow. Lisa also includes plenty of hot links pointing to online resources.
Check it out at: https://lisalouisecooke.com/2019/10/29/school-records-for-genealogy/