University of Florida and University of Minnesota researchers counted the number of alcohol ads within a two-block radius of 63 Chicago schools and compared students' opinions on drinking when they were in sixth grade and again two years later.

The study, published in the Journal of Studies on Alcohol and Drugs, found that the more ads for alcohol there were in a neighborhood, the more students were interested in drinking alcohol.

There were alcohol ads on storefronts, billboards, bus stop signs as well as other types of ads. In total, there were about 931 ads for alcohol around the schools. On average, there were about 28 ads in each neighborhood -- but one school had more than 100.