The correct verb would be impose. "Enforce" means to actually use an already existing rule, while "impose" means to create new rules. In your example, you said "more strict rules", (stricter would be a little better, more strict is ambiguous; we can't tell if you mean more (as in in increase in number) strict rules, or if you're using "more" as an intensifier.), so it has to be impose.
"More strict rules" would be additional strict rules. "Impose" would go with this phrase.
"Stricter rules" would be rules that are more stringent. "Impose" fits best with this phrase too.
To use "enforce", you would probably need to say something like "to more strictly enforce the rules concerning students' behaviour".
In any case, "rules on students' behaviour", or "rules for student behaviour" would sound more natural to my ear than "rules to students' behaviour".