Alex has a good answer. The problem with using negatives with these words is that there are two different ways you can change "all/each + negative verb" into a grammatical sentence, and each way has a different meaning. The two options are these: "None of the boys like it." (This means that there is NO boy who likes it. All the boys dislike it.) "Not all of the boys like it." (This means that SOME boys don't like it, but some boys do.) Here's a second example: "No boy has his own room." / "None of the boys has his own room." (This means that there is no boy who has a room.) "Not every boy has his own room." (This means that some of the boys have a room, but some boys do not.) If you say "every boy doesn't have a room," then it's not clear whether you mean that *none* of the boys have a room, or if you mean that *some*, but *not all* of the boys have a room.

It's better to say: "None of the boys have a room / won a prize" Not all boys like... = Some boys like it, but not all You could say "No boy likes..."

Not every boy receives a prize is more natural imo

In reply to your second question ("Is this sentence ungrammatical?"): Well, it depends on what you mean by "ungrammatical." I think some English textbooks use the term "ungrammatical" to describe any structure that isn't normally used in English, doesn't sound good, or is confusing to native speakers. The structure may not technically be grammatically *wrong*, but it sounds strange, and a native speaker would not use it. I think "every boy doesn't receive a prize" is an example of a sentence that isn't exactly "ungrammatical," but it also doesn't make sense. You want to give specific information about how many boys receive a prize, but no one can tell what you mean. I think the only time it would sound natural to use this structure is if you were repeating what someone else said (for example, in order to correct them). However, you would need to explain your meaning. For example, I can imagine a conversation like this: Joe: "I like this game, because every boy receives a prize." Mary: "That's not true, every boy *doesn't* receive a prize. In fact, only half of the boys receive prizes." or: Joe: "I like this game, because every boy receives a prize." Mary: "That's not true, every boy *doesn't* receive a prize. In fact, none of the boys receive a prize!" Mary is just repeating what Joe said, but adding a negation ("doesn't") in order to correct him. She then explains what she means. If she simply said, "In this game, every boy doesn't receive a prize," no one would be able to guess what she meant.