There are various reasons why power point should be banned from schools. There's nothing wrong with power point, per se, but professors who use it, tend to abuse it and use it in ways that are counter to a learning environment.
I took a biology class a few years back where the professor provided a powerpoint presentation for every class. We were supposed to print it out before class and then in class, he would read through the power point presentation. Literally, word for word, reading the presentation, with little or no additional information. Obviously, once I figured out this was his modus operandi, I stopped going to the clas, as I'm quite capable of reading a power point presentation myself.
The problem with power point is that it's presenter (teacher) centric. This is fine in some forums, but in a classroom, a class lesson should be student centric. Students should interact and ask questions. The lesson should go at the pace that the students can absorb it, not at the pace the teacher can present it.
If all that's required to learn the information is to read, then why even have a class? Just give the kids a book and send them on their way...