President Barack Obama looks over a remotely operated vehicle to help firefighters with ice search and rescue calls developed by Olivia Van Amsterdam, left, and Katelyn Sweeney, center, as he toured the 2014 White House Science Fair.

WASHINGTON — President Barack Obama confessed to feeling a little bit, well, unaccomplished.

There was the catapult-armed mannequin who shot three-point baskets, the 18-year-old cancer researcher and the second-grade Girl Scouts from Tulsa, Okla., with their Lego “flood-proof” bridge design.

“I’m such an underachiever,” Obama said after chatting with Eric Chen at Tuesday’s annual White House Science Fair. Chen, a Harvard-bound San Diego, Calif., high school senior, won grand prizes at the 2013 Google Science Fair and the Siemens Competition in Math, Science, and Technology for identifying new drug candidates for the treatment of influenza.

It’s an annual self-deprecating routine for the Harvard trained lawyer and 44th president of the United States, who happily recounts his personal challenges in the fields of science, technology, engineering and math.

“One year I accidentally killed some plants that were part of my experiment,” he told Tuesday’s White House Science Fair audience. “Another time a bunch of mice escaped in my grandmother’s apartment. These experiments did not take me straight to the White House.”

This year, Obama drew special attention to the science and engineering achievements of girls and young women, noting men outnumber women studying and working in engineering and computer science.

“Half our team we’re not even putting on the field,” he said. “We’ve got to change those numbers.”

Obama announced a new $35 million Education Department competition to train the best math and science teachers. He also announced and expansion of AmeriCorps to help teach science and math to 18,000 low-income students this summer, and national science and math mentoring projects in Chicago; Philadelphia; San Francisco; Allentown, Pa.; Indianapolis; the Research Triangle Park in North Carolina; and Wichita, Kan.

He noted he often greets champion athletes at the White House, most recently the Super Bowl champion Seattle Seahawks. But he said accomplished students deserve such honors, too.

“As a society, we have to celebrate outstanding work by young people in science at least as much as we do Super Bowl winners because super-star biologists and engineers and rocket scientists and robot builders, they don’t always get the attention that they deserve, but they’re what’s going to transform our society,” he said.