If you are worried that your child seems to be constantly restless and is not able to focus on school work, then the right course of action is to get the condition evaluated by a specialist.
At the same time it is imperative that you analyze the environment in which you are bringing up the child to understand where the behavior stems from. This is all the more important because lately there has been an undue hurry on the part of many specialists to quickly diagnose children with Attention Deficit Disorder or Attention Deficit Hyperactive Disorder.
If you are not monitoring the time and the quality of television programs that your child or toddler is watching you probably have no idea of the kind of effect that television is having on your child's attention. There is a great possibility that your child's short attention span is due to excessive viewing of inadequate television programs. The worrying part is that exposure to the television screen starts early in age and even infants are frequent viewers. Ideally, children below two years should not be allowed to watch television at all. Older children can be allowed to watch for up to two hours daily. However, the quality of the programs watched should be closely monitored. Watching flashy programs with no meaning does not stimulate the natural instinct of inquisitiveness in children. Educational programs arouse and activate the child's inherent aptitude of thinking and inculcate a habit of looking at situations in different ways and seek further information.
As an adult you would have realized that high quality programs affect you differently and the more you get involved with the subject the more it helps to improve your attention span. For example, you may not mind missing out on a dialogue or even a full scene in a soap opera dealing with sentimentalized family matters. But if the program is about, for example ancient Egyptian civilization, you would make sure that you listen to each and every word of the commentator. A child who sees such a program will be naturally curious about other ancient civilizations and ask you questions or want to see similar programs. Actually, this is one of the best ways in which you can improve your child's focus and concentration. On the other hand, programs that have no meaningful content simply engage the child in images and nothing else.
The same is true for the type of toys and the reading material that you bring for your child. There has been a growing tendency on the part of parents to choose what is attractive rather than laying stress on gifts that are thought provoking and help the child to learn.
Your help is of prime importance in developing long attention span in your child. You can also teach your child mental exercises that will help in controlling thoughts, better memory, and will power, freedom from anxious thoughts and help instill the ability of choosing his/her thoughts.