Not all kids with ADHD are constantly on the go.
We tend to think of them as being hyperactive and impulsive -- they're the ones squirming in their seat, tapping their pencil, grabbing things that don't belong to them, and causing trouble. And they seem to know only one speed: overdrive. Although these behaviors are indeed classic signs of ADHD, some kids with the disorder are relatively calm. Girls, in particular, are more likely to have a type of ADHD that primarily makes it difficult for them to pay attention. They often daydream and have a difficult time following directions and focusing on schoolwork. But because these children aren't disruptive, their ADHD often goes undiagnosed and untreated, says Dr. Fassler.