I have three kids (2 teenage boys) and, usually, put the bikes on racks on the roof of my TV, but that is a real hassle. I have been looking at folding bikes for the boys, and that would make it a little easier for (to and from) transport. They sell bags for them, but I just don't like the price of the folding bikes.
2007 Jayfeather 29X
2000 Ford Excursion V10