Most buses these days run on diesel which used to be more economically viable. I would love to get an older bus with a 12V Cummins diesel and turn it into a "Schoolie" to live out my retirement years!
Newer diesel engines have all of the DPF and other junk that make them downright unreliable and expensive to maintain! Trucks with the older pre-smog diesel engines are worth their weight in gold these days but they are not allowed in California and AOC and her ilk are trying to outlaw them elsewhere. Along with the skyrocketing price of diesel makes trucking unsustainable for the little guy and will eventually become an economic killer for everyone!
But yes, there are other ways to evangelize kids. I could not imagine anyone these days just sending off their kids in a Church bus though! Parents hardly let their pre-teen kids out of their sight as it is! I know I could never ask a parent to allow their kids to ride a bus full of ghetto kids who would probably bully and beat up those who were more vulnerable (this was the situation of which I was speaking of - nice, well-behaved kids had no business on a bus with kids who had parents who were crackheads, dad was likely in prison, being raised by a welfare mom, and in and out of the foster system!
Actually, if you want to reach kids, perhaps that last group would be the best way! Take in some foster kids and teach them the fear of the Lord! We did that for the last few years I was out in California and am still in touch with a few who came through our home.