Absolutely. When I was first starting out, I made so many poor design and implementation choices. I like to think I've improved tremendously since then, and I've only done so by putting in thousands upon thousands of hours of programming.
That doesn't matter. There are tons of things you could do depending on the goal of the hackathon. If there is one nearby to you I'm sure you can help.
I can't wait to see what people come up with.
RIP.