Going to south Goa on holiday?

Me and my boyfriend are going to South Goa april 2012, we have already put the deposit down however, I can not find much to do in the area. It is his first trip out of the UK and so I want it to be fun, We are 20 years old so dont really want to be doing all of the historical site, more fun things but not necessarily drinking related. If anyone can give some suggestions or good websites it would be much appreciated.