aiya I tell you, first three months will be the most shiok period in your jc life. don't need to care about work/cca etc.
everyday go school look at girls(i was from boy's school), make new friends and play soccer. after school go out lepak and stuff.
I went to CJ for first 3 months and it was damn fun but my studies were like crap. I got 4/50 for maths test and i ponned physics test.

But 2nd intake is VERY different. Im in SAJC now and it's damn stressful lah, homework keeps piling up like mad and PW really is as fun as stabbing yourself. The environment is COMPLETELY different as compared to first 3 months according to my friend who was in SAJC during PAE. I guess it's the same everywhere.
So just go to a fun jc during first 3 months, you won't regret it.

(okay I'll admit it, i'm a really bad example)