Most university map apps on Google's Play store seem to just use their university's logo or a generic map icon. Neither way seems ideal, but I'm unable to come up with a better way myself.
How do I come up with different ideas for an icon design?
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DA01 make a good point - If I'm looking for a map app for my college, I care more about how it looks on my home screen than whether or not it looks like other colleges, since I'll never be using those apps. Know the intent.
The biggest reason you'd want to differentiate is if you're going up against multiple map apps for your campus.
But let's say you do want to try to be creative and do something...this is a good thing, so long as it doesn't come at the expense of functionality!
A good way to brainstorm is to make a word list. Come up with as many words as possible that can be linked to the thing you're trying to represent. Once you get the obvious out the of the way you can get into some others that might be a bit more unique. So, in your case, think of words that describe your campus: geographic features, buildings, colors, mascots, traditions, etc. Think of nouns, verbs, and adjectives. See if there's something there that can be graphically represented. See if you can get to 50 words; the first 10 or 20 will be easy and obvious, and after that you start to find the unique stuff or start to sense some themes that you can work with moving forward.
Also, it might be good to look at all related icons in use and see if you can identify trends in imagery and color. Brands will do this so that they can either get in line with what's familiar to be familiar, or do something different to stand out. You mention generic map elements...what are these elements? Are more being used than others?
The point of these SE sites isn't to do work for you or help you brainstorm, so that's as far as I'll go. But I wanted to give you some principles that hopefully help you get started here and help you beyond this particular project.
It's more important for an icon to communicate its intention than it is for it to be terribly unique. The obvious ideas that come to mind would be a school logo on a folded piece of paper (map).
Other than that, though, you're basically asking us to do creative brainstorming for you. SE isn't the right format for that.