I used to work at a day care center for several years and every year, these sparrows would build a nest in the grill of the daycare van. When you came back from a bus run, the parents would be waiting there with bugs in bill, on the fence, to feed the babies. When the babies got too big, they would fall out as you were driving, so they never got to raise their babies all the way.
One year we took the grill out of the van and removed the nest. The eggs were hatched already. We tried to put them somewhere where the parents would care for them, but they wouldn't have anything to do with them anymore.
So we took turns taking the things home at night and feeding them several times. We got meal worms at the pet store and fed them with tweezers. The kids fed them during the day. It was a good lesson for them. All but one lived until it fledged and the sparrows never built another nest in the grill again.