Spend some time to write a business plan and try with all you've got to pitch it. Success or failure that is a worthwhile learning experience.
I guess I should have added more detail. We've written out a full business plan, it's just very weak (knowingly). We've pitched a few different times and just finished up a Business Plan competition at our school.
It was a fantastic experience and we learned an absolute ton (a lot of it being how much we did wrong from the start, but still very valuable). It's just so hard to tell the difference between "quitting" and spending your time more wisely, i.e. on a new idea.
5x different ideas x10 targets = 50x engagements, not out of the realm of an intensive time-suck. Could eventually lead to an alternate plan point of focus.