With USD 714 billion outstanding student-loan debt hanging over graduates in the US, it’s no surprise that more and more people are turning to free educational content on the web. Earlier this year we reported on Academic Earth, a US enterprise that makes lectures from Ivy League colleges free and accessible to all web users. Now, featuring over 1,500 videos the website is broadening its scope by offering courses for high school high-flyers. The new lecture series is aimed at students taking Advanced Placement (AP) exams, which give them a chance to study college level material and potentially earn credit towards their future degree. This year there are 10 video courses on offer, each featuring up to 50 lectures from MIT, Yale, Berkeley and Stanford. Subjects covered include computer science, calculus and psychology, and along with the videos there is also the option to download the lectures as podcasts. According to Academic Earth’s 23-year-old founder, Richard Ludlow, more AP courses can be expected in future years; in the meantime the site will be concentrating on providing supplementary materials such as lecture notes, transcripts and related books. Academic Earth is one of a flock of ‘edupunk’ enterprises on the web, ranging from peer-to-peer universities to fully-fledged state-funded institutions that award accredited degrees. Open content is going to play an increasing role in higher education, and with it comes a host of opportunities for social entrepreneurs.