I'm looking for a synonym for "curious" that is undoubtedly positive. "Curious" itself is fairly neutral--it could be interpreted as a good thing, but it's sometimes seen as a bad thing (i.e., "Curiosity killed the cat."). There are plenty of other synonyms that are wholly negative: "nosy," "snoopy," "prying," etc. Are there any other synonyms for "curious" that make it clear it's a good thing, such as to describe someone who's curious about an academic subject and wants to learn more about it?
I've already tried Webster.com's thesaurus search, as well as thesaurus.com and synonym.com, but the only results there are either neutral or negative.