If you want to draw further attention to your question, editing to improve it is one good way to go. However, doing multiple trivial edits to repeatedly bump the question to the front page is indeed frowned upon. If you see someone doing this, flag the question for moderator attention with a custom flag, or leave a comment expressing displeasure at the behaviour.
Catchy titles are relatively OK so long as they do describe the question. If they do start to stray into clickbait territory then you can edit it out for something that's more descriptive of the actual question. A title like "Solve it if you can" would be rather outside the envelope and should be edited in favour of something descriptive.
Regarding this, though,
Moreover such questions are irritating too (i.e. homework related)
the on-topic-ness of a question and the appropriateness of its promotion are independent. If it is irritatingly homeworky to a degree that makes it off-topic then vote to close (at 3k+ rep) or flag as off-topic. If it is irritating but on-topic, then sorry, it's earned its keep on the site. The rules on over-promotion via edits and titles apply regardless of the question type and content.