Q: As long as I don't say names of ppl, places or their age in a video about a teacher can I get in any kind of trouble?

A: Your question potentially has two primary issues to deal with in answering, the first concerns privacy rights the second involves defamation law.

While privacy laws vary from jurisdiction to jurisdiction and the law changes fairly frequently as well as rulings are difficult to predict because each fact pattern and the individuals and entities involve vary. This said, if you leave out names, addresses, etc., but people and entities such as the school are still identifiable you still may be running afould of the privacy rights. You would have to go to painstaking lengths to ensure the anonymity of the individuals and entities is preserved and that it wouldn't be traced back to them, that may ultimately be very difficult to do depending on the infamy of the individuals, entity, and events involved.

Now, as to defamation. Truth of the subject matter is an absolute defense. If you followed the election in 2016 you know that "truth" may be in the eyes of the beholder, in fact the term "post Truth" became popularized this past year. Even if every event you write about is true, the way you characterize it may be deemed inaccurate and subject you to a defamation lawsuit (libel if in print, slander if spoken). Of course the target of the defamation must actually be damaged by the comments, that's usually difficult to prove, but damages can be presumed if it relates to the employment or profession (see libel per se).

With all of the above said note that individual instances and circumstances vary, the above is general advising and as with most attorneys the primary goal is to advise concerning potential liability or pitfalls so that an informed decision can be made. Erring on the side of caution is the way most lawyers advise, that includes me.