In college admissions it is the year of unprecedented uncertainty.

Akua Abrah, a talented senior at Annapolis High School, tried to guess how many top schools she would need to apply to in order to get in somewhere she really wanted to go. She chose 10.

Admissions deans such as John Latting at the Johns Hopkins University walked a tightrope as they tried to estimate how many students to accept to fill their freshman classes. What was the probability that students such as Abrah, who might be accepted by competitors, would choose Hopkins?

A bump in the population - a so-called baby boomlet - means that a record number of high school seniors are applying to college this year.

Making matters worse, a handful of selective colleges dropped "early decision," so thousands of students who would have been committed to attend a college by December instead joined the larger group applying for spring acceptance.

And some counselors suspect that colleges began rejecting highly qualified students who the admissions officers believe are applying only because they need a backup "safety" school. National rankings judge colleges in part by the yield rate--the percentage of accepted applicants who ultimately enroll. So colleges worry about accepting too many students who decline to attend.