Group projects...
I feel for you. Here is my suggestion... Suggest that your group do a group/individual evaluation (on each other). If you don't think that will work, see if your teacher can implement it. The only group project that I didn't have to haul more than my share with was one where we evaluated each other and their contributions. Loved that professor, took another class with her (but the other class didn't have group projects). If they think that others will influence their grade, they may be more likely to pick up their share. If no can do, let the teacher know who isn't pulling their weight. Friendships are friendships, but a GPA lasts forever. Use your best judgement.