Yes, Girls Can Have ADHD Mary Adams, a 13-year-old from Orange County, CA, has always struggled in school. She’s shy, quiet, and often daydreams in class. Whether doing math homework or reading a novel, she needs double the time of her peers. But for many years, her teachers didn’t notice she was falling behind.

“They said, ‘Mary is smart, she’ll do fine.’ But she felt stupid,” says her mom, Shelley Adams. “She was 7 at the time.” At age 9, Adams got a private evaluation for Mary. After a 3-hour test, she was diagnosed with ADHD.

Like Mary, many girls struggling with ADHD (attention deficit hyperactivity disorder) go unnoticed by parents, teachers, and other adults. On the surface, they may be no different from other children -- getting easily distracted or forgetting their homework. But if these symptoms last longer than 6 months, it could signal a problem.

A growing body of research suggests the number of girls with ADHD is much higher than anyone thought even 5 years ago. Experts say the disorder affects boys and girls nearly equally, but more than twice as many boys are diagnosed and treated than girls.

Slideshow: ADHD in Children