Here's some info on our Free Trial Teacher accounts.
Free Trial Teacher account
Free Trial members can invite up to 40 users (a combination of teachers and/or students) to your classes. Students and teachers that are added to your class will not be given paid memberships, and will either need an activated free trial account, or have a personal membership in order to join.
Free Trial members have access to a limited selection of Challenges and Courses, and can assign them to their class. Students in your class that have a paid membership will be able to access all Challenges and Courses. Students in your class that have free trial accounts will only be able to access the limited selection of Challenges and Courses you assign.
Please note: with a 'Teacher Only' membership plan, teachers and students you add to your class are not given paid memberships. Users can independently purchase a membership for their own account, or you can upgrade to a Classroom and School Plan which can include up to 200 paid teacher and student memberships here