My nephew, at age 7, was diagnosed with ADHD. We could not understand his impulsive behavior and temper tantrums over the last few years. He would break things all the time in the house and would yell at his brother when frustrated. The "rigid thinking" part of the article hit home hard. Many, many times he would tear his homework up because he felt he was stupid for not understanding it. He would squirm in his chair and slide down the back of it crying. After going to the doctor and finding out what was going on, he has improved a lot. He is now 10 and has enrolled in special education classes and making great progress. His confidence has increased with improved performance.