It sounds like he's making up a shortfall of less than $200. If he teaches three classes of twenty students each, that's about $3 per student. Do you really think the average parent would prefer to save $3 per year, in exchange for ads on tests?

I was basing my comment on the scenario where privating schooling was "hyper-competitive", for example if it replaced public schools. So that would make a few assumptions:

1) Advertising could be done on a wider scale and more targeted (not just one class) making it more profitable

2) Once a well established system and relationships are made with advertisers they would make much more money per ad

3) In order for the school to remain competitive, they would need more resources to provide a better service, giving them an incentive to maximize revenue.

Based on that scenario it doesn't seem that unreasonable.

I say it's an acceptable cost if it results in schools' main product, education, sucking less.

We get always get so worked up everytime we see someone playing with a new media to advertise in.

Teens are hammered with advertising left and right all their life from every direction, I hardly think a tiny ad for a local dentist is going to drive them to the edge.

When kids in school start coming home with tattoos advertising local businesses, I'll start to worry.

Usually, at a test, a kid will be as focused as he/she will ever get. It is specially cruel to show adds to a kid in such situations because maximum attention is required for someone doing a test...