We get a lot of homework questions which get closed for lack of research effort. Many of these are otherwise good questions and it would be valuable to have these remain open in the long term. This question is on its way to being closed as homework. I think it is otherwise a good question, and I have written an answer to it. As a result I have saved my answer in a text file on my computer and commented on the question to request further effort from the OP.
"I have prepared an answer for you but, as this is homework, I would like to see more effort from you, some tips for you to think about: How do you think cloning could be used? Why would cloning be useful? Where can cloning step in? Why would this impact genetic variation?"
This gave me an idea. Could we have a formal mechanism to save an answer as a draft (currently there is a draft saving system) and set it so that if the OP makes suitable edits the answer is made public automatically?
There are two cases which need their own solutions:
1) The question is already closed as homework and therefore answers can't be written. We would need to add a feature such that questions closed as homework can still have answers written. Then when the answer is posted by the author it will display a message on the question, and notify the OP directly to the inbox, that an answer has been submitted and will be made visible if the question is reopened, and reminding the OP that the question may get reopened if they make the necessary edits. This will act as an incentive to the OP to make the requested edits, and will enable good questions to persist more easily.
2) The question has had 1-4 votes to close, including at least one for homework closure and is therefore still accessible to posting of answers. In this case the author of the answer can still write an answer, and could be given an option to "hide" the answer from view. Again the OP is notified and there is a message on the question requesting improvements to the question. When the OP makes edits to the question the author of the answer will get a notification to check the edits, and decide whether to release the answer for publication (or a public vote on whether the question remains blow the standards set).
Overall I think this would encourage OP's to make edits to questions that are homework; if they put in enough self-answer effort then they will get a good answer in return; good edits are surely more likely to occur if they know that there is an answer waiting for them. It's like fishing, if you put bait on the hook you're more likely to get a fish!
Note: perhaps queued answers could also be visible to high rep registered users (most homework comes from low rep or unregistered users), that way the answer can get feedback and votes, and still contributes to the site if the question remains closed in the long-term