When Amanda Wolfbauer, a high school senior, received the admissions verdict from Hamilton College, in Clinton, N.Y., she posted on Twitter, "What does one do once they’re on a college waitlist? #frustrated #)worsethanrejection."

A few minutes later she had gone from dejected to dogged: "Well, @HamiltonAdmssn prepare to be dazzled, because I’m determined to get off that waitlist."

Since then, Wolfbauer, of Carver, Minn., says she has written the admissions department to tell it "how much I want to go there and why Hamilton has been my No. 1 choice since the beginning of my college search"; she sent in "a lot of high school projects," including one that won a statewide competition; and last weekend she started filming a video with friends — teachers to be added later — "basically telling them how awesome I am, talking about the positive qualities I have and why Hamilton should accept me."

Does she ever worry it might be too much? "I more worry that I’m not doing enough," she said.

Especially not while other students on waiting lists are bombarding their dream schools with baked goods, family photos, craft projects depicting campus landmarks and dossiers of testimonials from civic and religious leaders, to name just a few come-ons that admissions offices have seen over the past month.

For most applicants to selective colleges, the letters that arrived by April 1 brought an end to months of anxious wondering. But for some small fraction of those students, the tension is only now reaching its apex. They were assigned not to the relief of the yes pile, or the decisiveness of the no pile, but to the slender median of the maybe, with no idea how their application will be resolved, or even when.

The schools generally ask those students to send word of whether they wish to stay on the waiting list or want to be removed from consideration.

"We encourage wait-listed students who remain very interested in Columbia to send a brief letter affirming that interest and updating us on their senior year," said Jessica Marinaccio, Columbia University’s dean of undergraduate admissions, "and discourage them from sending extra letters of recommendation or other supplementary materials."

Given the high stakes and the opaque proceedings, however, some students just cannot hold back.

Admissions officers describe the dynamic in terms that sound like dating: Hopeful students are trying to express their interest without coming off like a stalker, while colleges are trying to figure out whether the students are courting other institutions on the side.

"Last year, I had a girl who wrote to me every day," recalled Monica Inzer, Hamilton’s dean of admissions. "She’d send me emails; she’d send me letters; she had alums write to me. We all knew that this girl wanted us more than anyone else."

When three spots in the freshman class opened up, that eager young woman was the first person Inzer called. "She said, ‘Eh, I’m going someplace else."’

Another applicant eagerly informed Ann Fleming Brown, the director of admissions at Union College, in Schenectady, N.Y., that the college was her first choice — or had become that when her true first choice, Bowdoin, rejected her. It is just one of the many ways, Brown and her colleagues at other schools say, that students on the waiting list have shot themselves in the foot in recent years.

They have insulted the college’s judgment or taste. They have disparaged classmates who already got in. They have threatened to go over the admissions officer’s head. Showing up and demanding an interview is inadvisable. Showing up with a camping tent, even more so.

And parents are often part of the problem. "There’s a mother who emails me every third day — they must have timers on these things," Brown said. "There’s one parent who calls up and yells at me: ‘I can’t believe this happened! This is a horrible thing!’ And then he calls 10 minutes later and says, ‘I’m sorry.’ Then he calls and says, ‘I know you don’t like me. I’m being a complete pest."’

To cut down on behavior like that, says David Borus, dean of admissions at Vassar College, "We are very explicit in the communications we send out about what’s going to help you and what’s not going to help you, and we make it pretty clear that if you do do some of this stuff, you’re just going to tick us off."

What works? Generally, communications that are informed and mature.

"What most students will do is write, ‘I love you I love you I love you,"’ said Michael Motto, a former assistant dean of admissions at Yale University who now works as a private educational consultant in New York. "While those notes are charming and flattering and warm, these are academic institutions."

Letters that indicate a deep interest in the college’s scholarly offerings, he and others said, probably go further. (The cookies that a wait-listed applicant to Yale once sent in — spelling out Motto’s name and employer — did not do the trick. )

No matter what approach students take, there is no way to predict how many seats will become available. Right now, schools are counting up how many accepted students have decided to enroll. (Even that number is only a conditional answer, since those committed students could still get word that their first-choice school has plucked them off its waiting list, leaving an opening for a student on the second-choice school’s waiting list.)

Trinity College, in Hartford, Conn., which offers several hundred students a spot on its waiting list, eventually accepted around 30 of them last year. The year before, that number was zero. And the year before that, it was more than 100. At present, Hamilton, the school Wolfbauer has been trying to impress, does not anticipate taking anyone off the waiting list, though that could change as the months go on.

Given that uncertainty, Inzer says, "I encourage families to treat a waitlist offer a little bit like a lottery ticket — if it comes through and you win, everything’s great, but you don’t plan on it."

Inevitably, some families will ask about buying their way off the waiting list. At Inzer’s former employer, Babson College, in Wellesley, Mass., she said one parent went so far as to open a checkbook and ask, "What’s it going to take?"

According to Motto, at a time when top academic institutions now receive nine-figure donations, there is little point in even asking those questions.

"All parents say they know someone who’s made a contribution" that has turned a spot on the waiting list into a spot in the freshman class, he said. "Has it happened in some instances? I’m sure it has," but, he added, "I think a lot of it is rumor."

Which may be why some people turn to other sorts of currencies. During his time at Yale, Motto said, "Some parent called and offered to buy me two pizzas every week for a year if I admitted the person’s child." (No one got off the waiting list that year.)

An entreaty that Brown received last month, from a father of a student on Union’s waiting list, may just top them all. "I was offered free rotator cuff surgery," she said. "Or, alternately, carpal tunnel surgery. I said, Unfortunately I do not need either surgery. And he said, But you will."

© 2013 The New York Times Company