A Punahou School seventh-grader was at the White House this morning interviewing first lady Michelle Obama on national television about childhood obesity after winning a C-SPAN student video competition.

Matthew Shimura, 13, said last night that he planned to ask Obama about what the government can do to fight childhood obesity by improving nutrition and physical activity. (Watch the inverview here.)

Matthew won first place in the middle-school category in C-SPAN's Student Cam 2010 competition with an eight-minute video called “;Childhood Obesity: A Challenge Facing America.”;

He said he came up with the topic after thinking about how Furlough Fridays are affecting children.

“;I just thought about childhood obesity and how school lunches and exercise are being cut back,”; Matthew said.

He worked on the video for three months starting in October, devoting weekends and most of his spare time to the project.

The video was finished in January before Obama announced her national campaign to fight childhood obesity. Obama has been speaking out about ways to improve fitness and encourage better eating habits among young people.

Matthew interviewed his pediatrician and used footage from C-SPAN to create his video. At one point they were asked to stop filming at a McDonald's restaurant, his mother, Sharon Webb, said.

“;Ever since the fourth grade, we've been aware that he's really got a gift,”; Webb said. “;He goes out and shoots all this video and edits it in the basement.”;

Matthew said he first became interested in videos when he shot a movie as a school project in fourth grade. He also won a video competition sponsored by the Hawaii State Bar Association and wants to become a documentary filmmaker.

Cathy Kawano-Ching, the teacher who suggested he enter the C-SPAN contest, said she was “;surprised but not surprised”; that Matthew won.

While in sixth grade last year, Matthew organized a “;Local KINE (Kids in New Endeavors)”; film festival at Punahou to encourage students to create films that raise awareness of important social issues.

“;He's very talented. He sees things through the eyes, through the lens of a filmmaker,”; Kawano-Ching said.