Disney Channel has started working on the next installment of one of its most popular franchises "High School Musical". Peter Barsocchini, who wrote all three previous movies, will co-write the new project with Dan Berendsen.The channel has officially started casting for fourth installment, which will center on a new group of students at East High, as well as their crosstown rivals, the West High Knights. The announcement comes a decade after the first film debuted on Disney Channel and instantly became one of the network's biggest hits. The second film debuted one year later, followed by "High School Musical 3," which premiered in theaters in 2008.
