I'm trying to mentally place myself in how I'm reading the OP's situation.
If I'm understanding correctly, the OP sent out a bunch of information about the upcoming school year and it seems expected everyone to whom it was sent said "got it" or "thanks" or whatever to acknowledge it.
I am in education, albeit as college faculty, and I get over 100 emails a day. A lot of these are from students, and answering their questions is my first and primary priority. Everything else gets shuffled to the side.
I also get a lot of what I'd call email "blasts" that are sent to a large group of people. Often these contain things like policy changes or how-to procedures on how to handle things. Do I ignore them? No! I skim them to see how applicable they are to me(if it's about mold in a building I've never even set foot in, to be honest I don't really care), and if they are even slightly relevant I read them in detail.
The only time I'd actually respond would be if something were unclear, in which case I would respond with a question.
If an email is addressed directly to me, it's a different story, but that doesn't sound like the OP's email.
I regularly send out emails to other groups of people. Now I regularly email all the students in my class with important information. Back when I had managing teaching assistants(TAs) I'd send regular emails with information about the upcoming week, documents they needed, things I'd find out as the week progressed(this isn't working, do that from now on) or even to address general issues that were arising.
In all of those cases, I don't WANT responses from everyone. I don't need a dozen or more "got it" or "thank yous" or whatever in my inbox. 3 people saying "When you said X, did you mean do y?" is fine, but just answering for the sake of it is not a productive use of anyone's time.
To get at what
@mollyc was asking/discussing(if I'm understanding her correctly), the only time the phrase "Did you read my email" comes out of my mouth is if I see a problem that was directly addressed in an email. If I send Joe, Bob, Sally, and Karen an email that says "I need everyone to do x, y, and z before next Wednesday" and come Wednesday Bob hasn't done it, I talk to Bob directly. If it became a habitual problem with Bob, I might specifically request that Bob acknowledge the email or even send it read receipt to him(which I do use, but only occasionally for very specific reasons) but that would be it.
If I had a boss or even colleague that expected an acknowledgement of every group email sent, it would get old VERY quickly. I did once while I was in graduate school serve as a teaching assistant for a professor who was emailing I think 8 or 9 of us at a time and expected not only a response but a "reply all" to every email sent(although he laid that out clearly in the beginning). It was an absolute mess, and I was glad I was only in that assignment for a week.