There is barely any other illness or deviant behavior in conversation than attention deficit hyperactivity disorder. Children and teenagers with ADHD can't focus their attention over a longer period of time, except a task of great interest for them. Additionally those children tend to show an impulsive behavior. The H in ADHD stands for hyperactivity, which equals restlessness. These children are always in motion. They run instead of walking and even when they are sitting they wave around their arms an legs.
There aren't any easy explanations for odd behavior during childhood and adolescence. Additionally our understanding of childish behavior is constantly changing. Is a child allowed to be wild and loud? Is it allowed to blow off steam or should it keep it all inside? If you aks these questions, different generations (our parents and grandparents) will answer differently. They used to say there are children with a wild tendency and others are more quiet and they all used to be accepted just like that. Today the trend called "functioning". Who does not play along gets sorted out.
In some books it said that ADHD is an inherent and incurable illness. In reality the appereance changes with age. People who used to be restless, dreamy etc. might be just the complete opposite today. At this point no ADHD diagnosis would be set. But there could also be aggressivity or social isolation added to the symptoms. The most important perenquiste to overcome ADHD symptoms is family support and the therapy matching the clinical picture.
The fact that medication works as you wish does not prove there aren't any alternative explanations for the unusual behavior of a child or a teenager. The relief that Ritalin and similar drugs offer should not persuade us to ignore the bare essentials. The easy way might not be the better one. Not in every case drugs are the solution.
IT was said to let off steam