There is no single "High School Musical" show. "High School Musical" is a franchise encompassing several movies, a TV series ("High School Musical: The Musical: The Series"), and stage productions. To find out when the next showing of a *particular* High School Musical production (movie, TV episode, or stage play) is, you need to specify:
* Which High School Musical? (e.g., the original movie, the second movie, the series, a specific stage production)
* Where? (e.g., a specific theater, streaming service)
Once you provide that information, I can help you find the showtimes.