A suggestion about the buttons. If it shows all the functions you put under one category as soon as you put your cursor on it. It will be much clearer for users to see where everything is. At the moment, if I'm new to the site, I have to click on each button to find the function. For example, how do I know where creating a new lesson is if I'm new to the site? I have to go through each title/category. Instead of one click, it could be 2 or 3 for one function.