FWIW - my experiences are similar to yours, bg. The kids from Houston ISD have the least amount of preparation - the ones from the suburbs do much better, although none of them really have what I would consider a sufficient background in writing. I LOVE a returning student - one who has been in the "real world" and doesn't want to waste his/her time or mine.
One of the main ingredients for success is college is - attendance. My students don't believe me when I tell them that, but it holds true. It's the chicken and the egg, though - do you do better in a class because you always attend, or do you always attend because you are the type of student who makes the effort necessary to succeed? At any rate, I'm very proud of the fact that my daughter gypsyboots LISTENED to her mother, and the only class she missed this semester is when she had a conflict betweeen a freshman required seminar and her philosophy dialogue. She cleared it with the seminar professor, and attended her philosophy dialogue.
School work THEN play = happiness

Play THEN schoolwork = misery.
We were in danger of being on topic there for a moment!