When most people look at a school bus, they see a big heap of yellow.
But color must be in the eye of the beholder, because some school administrators say when they look at a school bus, they see a whole lot of green.

"Every school district is looking at where they can generate new revenue," says Lansing School's director of transportation Nathan Rowen.

The latest in the revenue-generating trends? Advertising inside school buses.

It's something a growing number of districts are doing to make money-- something Lansing schools have been looking at for two years.

"It's worth investigating," Rowen says. "That's not to say we're going to do it. We need to look at every revenue-generating purpose we can."

The popularity of this canary-yellow cash flow has the state Department of Education weighing in.

"We've had to scramble because there are no laws pertaining to this," says MDOE spokesman Martin Ackley. "We want to develop guidelines to help school districts make the right choices."

Those guidelines are, for the most part, pretty elementary.

"We want to make sure the messages promote academic excellence, safety, public service and good character," Ackley says.

Ads would be hung above the bus windows on the inside, and they'd come from a variety of advertisers that the districts would have to approve before putting them up here for the kids to see.

"You might see something from the Milk Producers of America telling you to drink milk, you might see something from the Navy or Army or Marines," Rowen says.

No "Fruit Loops" ads or provocative posters; but parents still might take exception to the blatant advertising their children can't avoid.

But as long as revenue remains an issue in schools, the wheels will keep turning for more money-making moves.

**Districts like Saginaw and Ypsilanti have already implemented ads in their buses and are seeing revenue from it.