Aubrey DiVito was deciding between playing basketball at Slippery Rock University and volleyball at California University of Pennsylvania when she received a letter from Liz Jones, the Robert Morris University crew coach, who had seen her at a basketball tournament.

Not only was she clueless about crew, but she was also a poor swimmer who hated water. She agreed to meet with Ms. Jones and walked away with a larger scholarship offer than she had received from either of the other two schools.

"I knew I could do basketball and knew I could do volleyball," she said. "This was physically demanding, and I like that sort of challenge."

The recruiting of Aubrey DiVito highlights an interesting twist in college athletics today: You don't need to have an all-star resume to be recruited to play sports, especially ones like women's crew.

With more than 2,000 American colleges fielding sports teams, scholarship money for athletes is plentiful. To capitalize on that, several businesses dedicated to connecting high school athletes to college scholarships have thrived for decades.

"It's a huge, huge business with a lot of money at stake," said Martin Rock, who owns the Western Pennsylvania franchise for College Prospects of America. "Our goal is to get them the most money possible."

Mr. Rock's organization, in business since 1986, and National Scouting Report, which is six years older, are the nation's two largest college recruiting services.

Some of Mr. Rock's clients end up at big-name athletic powerhouses such as the University of Pittsburgh and the University of Maryland. Others use their athletic skills to help them get into top-flight academic schools, such as Carnegie Mellon University and Dartmouth.

But most of them go to lesser-known schools that have money to spend on athletes, places such as Benedictine College in Atchison, Kan., and D'Youville College in Buffalo, N.Y.

To hit every possible school that might have money to offer, the services send their clients' athletic and academic profiles to every school in the nation that offers the client's sport. For football and basketball, that could be more than 1,000 schools.

Sam Gioia, a 2004 graduate of Bishop Canevin High School and a former client of Mr. Rock's, had never heard of the University of Rochester when he started his search for a place to play college baseball.

His family paid Mr. Rock $1,100 to make a videotape and mail profiles of his athletic and academic accomplishments to nearly every college in the nation.

His GPA, above 4.0 when bonus points for honors classes were included, stood out when Rochester's baseball coach was perusing profiles on the College Prospects Web site. By January of Mr. Gioia's senior year, the Rochester coach had arranged for him to receive an academic scholarship of about $24,000 a year.

Although the process certainly worked for Mr. Gioia, who stopped playing baseball after his freshman year, college coaches differ on the effectiveness of recruiting services.

"We've never gotten anybody from anything like that," said John Papa, who has coached track and cross country at Slippery Rock for almost 20 years and has only a few scholarships to offer. "When you get a kid from California, they're not coming to Slippery Rock. They're fishing for scholarships, so we're out of that market."

But Kim Kelly, the women's volleyball coach at Carnegie Mellon, said she contacts many of the high school girls whose profiles she receives in the mail. Although she fills most of her team with athletes who have contacted her personally, she said, she gets two or three a year from recruiting services.

Even counting Division III schools such as Carnegie Mellon, Mr. Rock said, his clients average $24,000 in scholarships when athletic, academic and financial aid grants are totaled together.

Full athletic scholarships are rare, he said, and are almost exclusively reserved for football and basketball players at top Division I schools.

Mr. Papa, the track coach at Slippery Rock, said he was dividing money for one scholarship on his men's team among about 10 athletes.

For that reason, most of the money Mr. Rock's clients receive is through academic scholarships, he said, adding that Division III schools are prohibited from giving athletic scholarships but are often willing to allot some academic money to athletes.

Academics are such an important factor in getting college scholarships, he said, that he very rarely takes on clients with grade point averages below 3.0, regardless of how accomplished they are athletically.

But while many scholarships come down to academics, others are heavily influenced by supply and demand. Put bluntly, some sports are more selective than others.

Men's basketball, for example, is probably the toughest sport in which to get a scholarship, Mr. Rock said. The maximum number of scholarships for each Division I school is small (13) and the number of high school boys playing basketball is in the hundreds of thousands.

In women's crew, on the other hand, there are about 2,200 high school rowers, but almost 100 Division I and Division II schools that offer scholarships.

"It's bizarre," said Ms. Jones, the Robert Morris crew coach, who has about three scholarships to divide among her women's team. "There are more scholarships than there are quality athletes [with rowing experience] who deserve a Division I scholarship."

To find rowers, she often looks for athletes such as Ms. DiVito: those who have no rowing experience at all, but have shown drive and commitment in other sports.

In the course of recruiting, she stalks big swim meets and basketball tournaments. In the 10 years she's been coaching, she has found athletes through word of mouth in church, and even through a comment her father made to a high school track coach on a golf course in New Jersey.

Women's crew is the most dramatic example of a supply and demand imbalance, but there are others, particularly in women's sports. Under the federal government's Title IX rules, the number of scholarships in women's sports has be proportional to the participation of women athletes.

That's why scholarship-hungry mommas should let their daughters grow up to be golfers, said Ronald Vrana, the Western Pennsylvania licensee for National Scouting Report.

"Find me a girl that can shoot under 100," he said. "I can get her a scholarship."