After the obligatory week or two of post-finals laziness, summer can be a great time to pick up new skills. Want to learn a new programming language? Spanish gotten a little rusty since freshman year? Here are five sites that let you learn without leaving the couch.

1. Khan Academy

Founded by Salman Khan in 2006, this non-profit website now boasts over 4,000 education videos covering topics from finance to animation to art history. Each video is about ten minutes long and begins with a blank screen that the narrator (Khan himself in over 3,000 of the videos, according to Forbes) draws on in bright colors to illustrate concepts. Khan’s style is surprisingly easy to follow. “I teach the way I wish I was taught,” Khan says.

2. Skillshare

Skillshare’s tagline is simple: “Learn Differently.” This site proposes a new kind of model for online education—anyone can sign up to take a class, and anyone can sign up to teach one. Instructors determine a price for their class (usually fairly low, around $15-$30) and decide whether they want to teach in person or apply to teach an online global class.

The site has an incredibly wide range of offerings. A couple of courses that caught my eye: Grace Bello’s “How to Write a Killer Magazine Pitch” (99 students enrolled so far) and Anne Ditmeyer’s “Mapmaking: Learn to Communicate Places Beautifully”(870 students).

[cta_widget block=”cta-online-a”]

3. Codeacademy

“Education is broken. Come and help us build the education the world deserves.” Codeacademy’s mission statement is blunt. But it isn’t wrong. America’s educational system needs a reboot, and Codeacademy offers a viable solution.

Like Skillshare, Codeacademy offers courses created by users for users. Codeacademy’s home page features “tracks” that allow students to pick up programming skills from the ground up via simple tutorials and interactive exercises. Along the way, users earn badges and increase their total score. The gamified aspects of the site make it kind of addictive and far too much fun for something educational.

4. Lynda.com

For $25 a month, users can get unlimited access to lynda.com’s library of over 1,800 video courses covering a variety of subjects. The site’s software tutorials are particularly useful when trying to brush up on a program you haven’t used in a while, or learning the particulars of a newly released version of an old favorite.

According to co-founder Lynda Weinman, the site can help users keep their skills up to date. “It can be the difference in getting a new job or getting an advancement in your job or achieving the things that you want to achieve today,” she says in an introductory video.

5. EdX

Founded and run by educational powerhouses Harvard University and the Massachusetts Institute of Technology, EdX features “learning designed specifically for interactive study via the web.” The site currently offers online courses from Harvard, MIT and Berkley, and plans to include classes from Wellesley, Georgetown, and the University of Texas in the fall.

Though the site claims to hold students to the high standards the schools involved are known for, users receive certificates rather than credit for completing courses.  I’ve included EdX here because it has a number of classes listed for this summer, but it’s worth nothing that MOOCs (massive open online courses) are available through a number of programs, including (as of this spring!) the iSchool.