For years, those states have heard complaints that not enough of their lottery revenue is used for education. Now, a New York Times examination of lottery documents, as well as interviews with lottery administrators and analysts, finds that lotteries accounted for less than 1 percent to 5 percent of the total revenue for K-12 education last year in the states that use this money for schools.

In reality, most of the money raised by lotteries is used simply to sustain the games themselves, including marketing, prizes and vendor commissions. And as lotteries compete for a small number of core players and try to persuade occasional customers to play more, nearly every state has increased, or is considering increasing, the size of its prizes — further shrinking the percentage of each dollar going to education and other programs.

In some states, lottery dollars have merely replaced money for education. Also, states eager for more players are introducing games that emphasize instant gratification and more potentially addictive forms of gambling.

Of course, the question of how much lotteries contribute to education has been around for years. But the debate is particularly timely now that at least 10 states and the District of Columbia are considering privatizing their lotteries, despite assurances decades ago that state involvement would blunt social problems that might emerge from an unregulated expansion of lotteries. These trends fly in the face of marketing campaigns that often emphasize lotteries’ educational benefits, like a South Carolina lottery slogan, “Big Fun, Bright Futures,” or an ad campaign in North Carolina featuring a thank-you note passed through schools and signed “The Students.” The New York Lottery’s Web site includes the tagline, “Raising billions to educate millions.”

Promotions like these have taken root. Surveys and interviews indicate that many Americans in states with lotteries linked to education think their schools are largely supported by lottery funds — so much so that they even mention this when asked to vote for tax increases or bond authorizations to finance their schools.