I would assume that the parents are working. I was frantically trying to think of kids I knew that age to put them at ease and my cousin has kids in that school that age. But then it occurred to me that I shouldn't really be making it comfortable for them. I drive that route every day in the winter, I wouldn't have my 15 year old walking to school in that weather. Granted these children where bundled up, snow suits, hats, gloves the whole nine yards (although younger one was wearing sneakers and carrying his winter boot lol).

I've thought about giving the kids a note to give to their parents letting them know that I would be happy to pick them up on my way back, but I don't want them getting into trouble either for getting into a stranger's vehicle, but then on the other hand it's not safe for them to get into just anyone's car.