My son just finished his sophomore year. 4.0 student, pretty self driven and will definitely study within a program. I have been looking at some of the options, including:

Princeton Review: expensive, but lots of options
Kaplan: I don't think my son wants anything to do with live courses (not his thing), but they do offer other options
Kahn Academy: Free, but completely self-driven without much structure
PrepScholar: Massive amount of material (good and bad I guess), money-back guarantee (160 point increase)
Magoosh: Good value, 12 months for $129, email help, nice pace when a student has a longer amount of time to study, 100 point increase guarantee

I'd appreciate any thoughts in this regard. I will likely post again later to talk about scholarship options. That's another area I am interested in learning more about. I appreciate any info people are wiling to share.