I was hired as a career intern with the DOE's Inspector General. It's a good gig because you get paid while you learn. One thing I would have done differently was to research the program before I signed on. The reason I say this is that there are a lot of recruitment incentives available that were not offered to me; I would have gone for the tuition reimbursement but didn't know to ask for it.
GPAs are probably not that strict but the government wants the most bang for its buck; mediocre employees are what it has now. Your friend should visit the various government web sites (http://www.doe.gov, for example) and notice that there are opportunities with the numerous contractors who do business with the federal government. Your friend also needs to get serious, study hard, and excel in courses now because that will prepare him/her for the level of effort required in the workplace.