Having spelled "serrefine" to win the Scripps National Spelling Bee, Evan O'Dorney is ready to tackle an even more unusual challenge for a 13-year-old boy.

"In the fall," said his mother, Jennifer, "he'll be taking calculus."

Evan, a home-schooled eighth-grader from Danville, Calif., breezed through the competition Thursday night to become the nation's top speller. He said he knew the winning word — a noun describing small forceps — the moment the pronouncer said it, but he was more enthusiastic when he spoke about an upcoming math camp this summer and the calculus class he'll be taking at the University of California at Berkeley.

"My favorite things to do were math and music, and with the math I really like the way the numbers fit together," he said. "And with the music I like to let out ideas by composing notes — and the spelling is just a bunch of memorization."

Evan won a tense duel with Nate Gartke of Spruce Grove, Alberta, who was attempting to become the first Canadian to win the 80th annual bee. Evan and Nate went head-to-head for three rounds, matching each other's correct spellings until Nate flubbed the medical word "coryza" by adding the letter "h."

Until then, Nate had been quite the showman, waving celebrity-like to the audience after each word and basking in the cheers from a row that waved red-and-white maple leaf flags.

"I didn't know I could make it this far," said Nate, who planned to cap his week in Washington with a tour of Mount Vernon on Friday.

Evan, who tied for 14th last year, won $35,000 cash, plus a $5,000 scholarship, a $2,500 savings bond and a set of reference works. His victory came even though he wasn't able to stick to one of his superstitions: He didn't have his usual pre-competition meal of fish because chicken was served instead at the Spelling Bee dinner.

Asked if he liked the bee more now that he's won it, Evan said: "Are you saying I'm supposed to like it more? Yeah, I do a little bit."

Evan's father, Michael, is a subway train operator in the San Francisco area. His mother, Jennifer, is in charge of Evan's schooling. Jennifer said Evan's spelling prowess has given him some balance in a life that's been dominated by the love of numbers.

"I believe it's made him more well-rounded," she said.

Evan was virtually unflappable on stage. The kid who juggles balls around the room at home while his mother calls out words appeared to be in trouble only once during the finals, when he had to restart "schuhplattler" a German-based word describing a dance. At one point, Evan calmly cleaned his glasses while Nate spelled a word.

The day began with 59 spellers remaining from the record 286 who started the competition Wednesday. The field was narrowed to 15 finalists, but eight were gone after the initial round and two more faltered in the next round, leaving a fivesome of Evan, Nate, 14-year-old Joseph Henares, of Avon, Conn., 13-year-old Prateek Kohli of Westbury, N.Y., and 14-year-old Isabel Jacobson of Madison, Wis.

Joseph faltered on "aniseikonia" (a visual defect), while Prateek missed "oberek" (a Polish folk dance) and Isabel was out on "cyanophycean" (a kind of algae).

The big surprise was that perennial favorite Samir Patel wasn't around for the finals. The 13-year-old Texan, in his fifth and final bee because he can't participate once he's past the eighth grade, had the audience gasping in disbelief when he misspelled "clevis."

After placing third, 27th, second and 14th in his previous bees, Samir ended his bee career with a tie for 34th. He wiped away tears as he talked about his gaffe.

"The first thing I thought was c-l-e-v-i-s, and if I had been slow and cautious like I always am, I would have got it right," he said. "But I just outsmarted myself. It was an easy word. I just made a stupid mistake."

Samir's mother, Jyoti, appealed his dismissal, based on subtle differences in the way the word's final syllable could be pronounced. The appeal was denied.

"In the end, I think I said it right," pronouncer Jacques Bailly said. "I really wanted him to get it right, and I'm really sorry that he or his family have some questions about it."