Some children who write poorly may have bad eyes. Poor vision can cause headaches that distract a child from the task at hand or even fatigue, which then results in poor handwriting. If you suspect your child is having trouble with his eyes, it is important to have his vision tested. If your child's handwriting is poor because he can't see and is easily fatigued, fitting him with eyeglasses may remedy the problem.
Some children have sensory issues. If your child has a sensory disorder that causes her to want to hold her pencil too tightly or not tight enough, this can affect the writing process. Children who grip the pencil too hard or press extremely hard on paper may create fatigue in their writing hand or produce illegible writing. In some cases, occupational therapy may be required to help your child deal with her sensory issues before handwriting can improve.
Attention Deficit Hypersensitivity Disorder causes children to lose focus easily. A child with ADHD can have severe issues with handwriting. According to the National Center of Biotechnology, ADHD causes hypersensitivity, inattentiveness and impulsive behavior, all of which can contribute to poor handwriting. ADHD can be treated with medications under a doctor's care and should be treated as soon as it is diagnosed.
A number of health situations that can result in poor handwriting. These include Asperger Syndrome, dyslexia, autism, dysgraphia, which cause children to have a low level of motor skills necessary for neat handwriting. Meet special needs circumstances with medical treatment as soon as possible.