Alright so here's the situation, I am taking a Computer Applications class. And we have been studying html code and php code along with a little bit of MySQL. We now have to make a website where we create a web app (like a calculator basically) I have pretty much already written my code to make an "asset=liabiliaties and owner's equity" calculator for the php and html so far and now I am trying to find a free website builder/domain service where I am allowed to write my own code into but also be able to use some of the builders template and such forth.

If you happen to have any suggestion or even previous expertise in this area please help.

Try Punbb forums. It's free. :3 It may not be the best, but I think that could help you.
And you could also try freewebs. (I think that's what it's called.)

Ok thanks I will look into those, didn't think freewebs had php for free users but I will double check. Again thanks :)

U can check out this [you must login to view links]
It uses HTML5 and is user friendly. U can choose from different templates.
I hope u find it useful