Recent news that the Rosemount-Apple Valley-Eagan school district might soon allow commercial advertising on its website is not surprising. Financially strapped districts are considering lots of nontraditional options these days to boost their bottom lines.

So when companies come calling with five- and six-figure ad plans, school leaders are understandably more open to listening. Yet before Minnesota school districts start counting that extra cash, they should carefully consider each case to determine what's appropriate for schools and what should be avoided.

Rosemount school officials have a list of things ads may not promote, including drugs, weapons and political viewpoints, and their principals can reject advertising if it is misleading or conflicts with district goals. The Anoka-Hennepin school board recently adopted advertising policy guidelines that could at some point include web promotions, but bans most direct solicitations.

And Minneapolis school rules forbid web ads and stipulate that, "Selling or providing access to a captive audience in the classroom for commercial purpose is exploitation and a violation of the public trust.''

As school officials consider accepting Internet ads, they'd be smart to think about the challenges presented. A company link on the district website could be changed several times a day or offer a second or third link to something improper. Some companies have asked districts to wrap school lockers with ads to earn as much as $1 million. That's clearly over the line in an educational environment. Students should not be forced to see huge, splashy ads every time they go to their lockers or walk down a hallway.

Despite the growing attention, commercial advertising is not new territory for schools. National experts say many districts have at least a toe in the advertising pool, allowing things ranging from banners at athletic events to theater program ads and plaques recognizing a business for buying team uniforms.

For years, many Minnesota districts have cut deals with soft-drink companies to exclusively carry their products in vending machines. In 1998, Osseo school leaders signed on with a beverage company for nearly $485,000 over 10 years in exchange for an exclusive shot at its students and staff.

But at that time Osseo leaders, not soft-drink sellers, exercised complete control over the ads. No advertising was allowed beyond the machines, and school officials determined their numbers and location. Many districts now demand that vending machines also include water and other noncarbonated drinks.

That's the right approach. If districts open the door to more in-school advertising, decisions should be made based on what's best for students and learning.

As a business that depends on advertising, this newspaper would be the last to condemn the industry. A private business is one thing, but minors in taxpayer-supported public schools are another. Between ages 7 and 16, Minnesota children are required to attend school to be educated -- not inundated with marketing messages.

More commercial temptation almost surely lies ahead for educators as they struggle to balance budgets. But as officials ponder the appropriateness of ads, the guiding principle should be to keep selling as far away from learning as possible.