The phrase "period class" refers to a specific class or period of time in a school day where students attend a particular subject or activity. It usually lasts for a set amount of time and can vary from school to school. Full definition
The second period class was at the other end of the behavior spectrum. (educationworld.com)
An inexperienced eighth grade language arts teacher relied on yelling, arguing with students in class, and writing office referrals to manage her fifth period class. (seenmagazine.us)
My high school offered only a single one - period class of computer science. (verywellfamily.com)