Is there going to be a high school muscial 4?

As far as my knowledge goes, which is limited to information available before September 2021, there are no plans for a fourth movie in the High School Musical franchise. The third film, High School Musical 3: Senior Year, was released in 2008. However, there have been several spin-off series, such as High School Musical: Get In the Picture, which aired on Disney Channel from 2009 to 2010. You can check the official Disney website or other up-to-date sources to see if there have been any recent developments regarding a potential High School Musical 4 movie.