SAN DIEGO (AP) - A California high school math teacher is adding up dollars from ads he sells on his tests.

Tom Farber came up with the idea to compensate for cuts in school funding for supplies. A calculus teacher at Rancho Bernardo High School in San Diego, Farber quickly calculated that the cost of printing his tests would be way more than his budget.

So he started selling ads that he prints on quizzes, tests and final exams. He says any money he doesn't use he'll share with the rest of the school.

Farber says the ad "definitely has to be non-controversial" and has to have "appropriate products for kids."

For those who might criticize his fund raising, Farber suggests they "go to their nearest school and give that school $1,000."

(Copyright 2008 by The Associated Press. All Rights Reserved.)