The study group of 3 or more at law school is even worse than undergrad. The problem is, especially the first semester before grades come out, EVERYONE thinks they'll be in the top 10% (or, if they have ZERO self-confidence...top 25%) and so EVERYONE feels like they need to say something on the tiniest of issues because they feel that they are super smart. Additionally, no one will want to be wrong, and since a lot of law is somewhat theoretical, you can have endless debates that will not help you at all come test time. And, if you dont have any problems with whatever principle is being debated, you just have to sit back and hang on for the ride...except that you feel like you're pretty smart too, so you end up joining in when there is any type of break in the converstation.
As was said before, I reccomend studying with one other person. That way you can bounce ideas off each other and correct minor misconceptions you dont even realize you have on certain legal principles. It can make a big difference.