It depends, when it comes to computer science, online classes are usually more convenient. This is because online classes in programming often require a lot of practice and having a PC at hand is always handy. In online classes, the tutor can also pass you web pages or show you lines of code, thanks to the screen-sharing function. Online tutors are often used to distance learning, so they will know how to keep your attention and make studying computer science and programming interesting and engaging.