Well, as a freshman in my second semester, I have some ideas from what I observe and my own experience:
1. How to manage time. (Ideas on how to make a schedule and stick to it, how to prioritize, how to know when we have to do every word of the reading or when it will be okay (due to there not at times being enough hours in a day to accomodate all of the reading) skim or just read what is essential for questions.)
2. I would want to know how much time I have to figure out what exactly I would like to major in and if it is essential to know my major right when I get to college, do all schools offer an undeclaired listing and for how long are students allowed to be considered undeclaired. (I remember when I got here I was unsure of this, although, my advisor let us know this.)
3. What are classes generally like, are there differences from classes in high school and if so, what are these? (I've noticed some differences and I would have liked to know about them before coming here.)
4. Maybe find some myths about college and then point out what is actually true.
5. Emphasis on the fact that college is not all that it is appeared to be in TV/movie shows (parties, fun etc.) emphasis on there needing to be time to study and time to have fun and the dangers of having to much fun and to much studying (basically students need to have a balance of studying and fun.)
That is all I can think of for now but if I think of anymore, I will let you know.