One of my classes requires me to buy a textbook. Okay, that’s fine. You can even buy the ebook.
You need the book to log into the website – each book comes with a unique code. If you buy it second hand, you can’t log into the website. That website gives you a test – a very, very basic test, it seems. If you pass the tests on the site, you can score 30% for your mark – but if you fail, you still get 15%.
If you don’t buy the book you don’t get that 15%. You get 0%.
Now, ignoring the value of the book, that feels very very suspicious.