Sack races and marshmallow guns? Silly season at the White House

The president is firing marshmallows across the East Room. Michelle Obama is engaged in a tug of war in the Diplomatic Reception Room. Just what is going on at the White House these days?

It turns out that the administration’s goal of boosting vocations in the fields of math, science and engineering isn’t the sexiest topic for reporters covering the White House. And the first lady’s push for healthy eating and exercise is hardly a new story.

So, the first couple is shedding some of the formality of their posts to generate new interest for some of their pet projects. And it’s getting some results.

On Tuesday, Obama hosted the annual White House science fair, and personally inspected some of the award-winning projects from youngsters across the country. One of his favorites was from 14-year-old Joe Hudy, an air cannon that he used to shoot marshmallows.

“Let’s try it!” Obama said after Hudy explained his work. “This is great!”

In two centuries, the East Room has been the scene of countless solemn, formal and celebratory occasions. And so the president seemed to have a mischievous appreciation for the fact that he was now firing sweets across the span of the room.

“The Secret Service is going to be mad at me about this,” he joked.

Just a week earlier, Michelle Obama was hopping in the very same spot in a potato sack race with “Late Night” host Jimmy Fallon. She invited the comic to compete in several physical challenges -- push-ups, a tug of war, hula hoops and even dodge ball -- at the White House to mark the second anniversary of her “Let’s Move” initiative.

The first lady won.

“The most important thing for the kids to learn is that it’s all about being active and having fun. It doesn’t matter if you won or lost,” Fallon says. “It matters,” Michelle Obama fired back.

Here’s the White House’s video of the marshmallow launch, and NBC’s of the “Let’s Move” challenge.