This screencast actually came from a request from students that their teacher brought to me. Apparently in years past it was quite a process to install fonts on the laptops. With the new MLTI MacBook Airs, it is super easy. The key is to find the file that you downloaded, which defaults to the "Downloads" folder in your finder menu. If the file is a .zip, you should be able to double click on it to "unzip" it to a regular folder. Once you open the "unzipped" folder, double click on the .ttf file and it will open in the Font Book. Clicking on the button in the bottom right hand corner of the font book will verify and install the font. From there, you should be good to go.
I had a teacher ask me if there was a way to hide or remove students who are no longer in your class. The answer is maybe. It depends on if they are officially dropped from your class and appearing as red in your roster and gradebook. If not, then no, you cannot remove them until they have been unenrolled from the class. If the student is showing up as red in your gradebook though, you can hide them so you don't have to worry about them. Here is a screenshot to help you do it: