When you buy, rent, or borrow a streaming film or DVD, of a movie, TV show, or any other audiovisual work made by someone else (referred to here generally as “film” for short), you normally obtain only the copy, and not the underlying copyright rights to the film. You are free to watch the film yourself, or with your family and a few friends, but most things beyond that are prohibited by law. You do not have the right to show the film to “the public.” In most cases, doing that requires a separate “public performance” license (often referred to as "PPR" short for "Public Performance Rights") from the copyright owner.
To determine whether you need a license, you must determine whether your film screening would constitute a “public performance.” If it does, there may be exceptions that would allow you to proceed without a license.
YES -- you need public performance rights:
NO -- you do not need public performance rights:
(Guilford Library)
Even if your proposed screening will constitute a “public performance”, you still will not need to obtain a license if any of the following is true:
"Nonprofit educational institutions can record television programs transmitted by network television and cable stations. The institution can keep the tape for 45 days, but can only use it for instructional purposes during the first ten of the 45 days. After the first ten days, the video recording can only be used for teacher evaluation purposes, to determine whether or not to include the broadcast program in the teaching curriculum. If the teacher wants to keep it within the curriculum, he or she must obtain permission from the copyright owner. The recording may be played once by each individual teacher in the course of related teaching activities in classrooms and similar places devoted to instruction (including formalized home instruction). The recorded program can be repeated once if necessary, although there are no standards for determining what is and is not necessary. After 45 days, the recording must be erased or destroyed.
A video recording of a broadcast can be made only at the request of and only used by individual teachers. A television show may not be regularly recorded in anticipation of requests—for example, a teacher cannot make a standing request to record each episode of a PBS series. Only enough copies may be reproduced from each recording to meet the needs of teachers, and the recordings may not be combined to create teaching compilations. All copies of a recording must include the copyright notice on the broadcast program as recorded and (as mentioned above) must be erased or destroyed after 45 days." Stanford Copyright Guide