When you confirm the lesson as completed, you are prompted to give a star rating and leave a review. The prompt is super obvious, so I’m guessing you’ve never confirmed a lesson. That’s OK, since the lessons will automatically be confirmed after 72 hours. (It used to be a week, but some teachers got tired of waiting a “full week” for students who never confirmed. Personally, it makes no difference to me. In the business world, clients get 30 days to pay, and it's not as if the site paid out every single day, so what’s another 4 days in the grand scheme of things? That said, some teachers will appreciate it if you confirm at your earliest convenience. I couldn’t care less about that, but I really do appreciate all the reviews, although in my opinion, it’s not necessary for long term students to write one after every single class.)