"Positive" synonyms for 'problem' or 'worst'

I need to find a positive synonym for 'problem' or 'worst' for some copy I am writing. The context is that these are ratings for student performance in a tabular format (as in, "problem topics: lorem ipsum" or "worst topics: lorem ipsum"), and while I want to indicate that the topics I am describing need improvement, I don't want to sound overly negative.

There is a good chance that the students have had exposure to basic economic theory, so I am considering "marginal" (especially since the topics being described are being prioritized to maximize the marginal benefit of studying). But this does not seem to be a standard usage. In fact, outside of economics, marginal seems to indicate the opposite of what I'm looking for.

Any ideas?

Solution 1:

You're looking for euphemisms. The business world is prepared to support you! :-)

Traditional euphemisms for "problems" are "challenges" or "opportunities".

Euphemisms for "worst" could be "low-hanging fruit" or "easiest target" or even "top priority"

Solution 2:

It appears that you're looking for phrases that indicate change is needed, but have a neutral tone; you're trying to avoid sub-standard, mediocre, etc.

Next steps is a good fit to indicate that something needs work, but doesn't have an overtly negative connotation.

An equally bland phrase is areas to focus on.

This is my least favorite, but it might be what you're looking for. If you need three concise column headings, it's possible that: excellent, good, other might be okay.