I attended the Landmark College summer program for High School students a couple summers ago, and yes know the two are different programs. Overall I'd say my experience with the academic program was that I ended up not gaining any study skills and this is pretty much my own fault. In reality, I'm sure at lot of people improved the academic skills, but what important is that you want to improve your skills and actively seek help from faculty. Finally, it's REALLLY expensive, so if you're going just to learn how to succeed academically in college, I'd look elsewhere.
I'll post some more experiences later when I have more time but basically the Landmark Summer Camp is just summer school and camp in the same thing, you can go for both, one or the other or neither it's up to you.