I gave up because it wasn't that useful and I can do something simpler that's faster to create while making money off of it.
It would be much more useful if most textbooks had an API or if teachers required for everything to be typed. The latter is not something that can be asked because there isn't anything out there that's good enough for public high schools to use (some students also don't have computers with a reliable internet connection).
There were some minor UX issues with it as well, but that's mostly it.
Have you looked into solutions with deeper integration? I am thinking of WebAssign. iirc they work with the textbook publishers to give more integrated problems (i.e. they would take a textbook problem like "What is the derivative of cos(3x) with respect to x" and would make 3 a magic variable such that each student would see a different problem such as "What is the derivative of cos(4x) with respect to x" or "What is the derivative of cos(5*x) with respect to x")
I would create something better than a textbook before working with textbook publishers. A decent chunk of the reason school is boring is a because of their work.
1. Download zip: https://github.com/Jarred-Sumner/Jantire/zipball/master
2. cd into the directory and run "bundle"
3. Sign up for the scribd API: http://www.scribd.com/developers/signup_api
4. Get your API key and API secret: http://www.scribd.com/account/edit#api
5. Add these to "config/initializers/rscribd.rb" along with your login information on line 5 ('email','password')
6. rake db:migrate
7. rails c: c = Course.new(name:"Biology").save; User.new(email: "example@email.com", password:"password", password_confirmation:"password", teacher:true, first_name:"John",last_name:"Smith", courses:[c]).save
8. rails s; open 'localhost:3000'
9. Login
10. ???
11. PROFIT
Screenshots: http://imgur.com/a/fIxNN#0