Brightstorm, an online education site aimed at high school students, has raised $6 million in a first round funding from Korean-based venture firm KTB. The San Francisco company told paidContent that its site is about to emerge from beta and is ready to launch an “online learning network” complete with video courses. Brightstorm hopes to attract teachers, parents and, most importantly, teens to the site for lessons in math, writing, history and AP and SAT test prep. In addition to all that, Brightstorm’s learning network also features quizzes, study guides and forums.