With kids heading back to classes and all the back-to-school shopping done, you may be feeling a bit inclined to learn something new yourself. You’re in luck! You can “go back” too, though it may be a bit different.Unless you’re rich or academically gifted, it’s unlikely you’ll take classes at universities such as Stanford, Yale or Princeton. These are some of the most respected universities in the world, and they charge eye-popping tuition to match their reputations.Of course, all universities charge a lot these days, whether that’s Brown University, Penn State, UC Davis, or the universities where you live. Yet, there is a way around steep tuition.Coursera is a great way to take classes at 140 universities in 28 countries. And the best part? You can sign up free of charge! These are professor-instructed classes, such as Algorithms (Princeton), Calculus (Ohio State University), History of Graphic Design (California Institute of the Arts), Photography Basics and Beyond (Michigan State), or many others.These are online classes you can take in your spare time, although there is usually a time frame to complete assignments and tests. There’s help, too. You can chat online with students around the world who are taking the same class.From the site, choose the type of class you’d like to take, such as Computer Science, Math, Language and others. Then, select a specific class, like Calculus I. That one, from an Ohio State University math professor, is 25 hours long, with videos and quizzes.It’s easy to sign up. Just input your Facebook credentials or sign up with your email address. Press “Continue” to get started.