The National Center for Learning Disabilities recommends testing for a student showing some of the characteristics below. Remember that the testing should be done by a qualified professional trained in the assessment of learning disabilities.
Often spelling the same word differently in a single document
Reluctance to take on reading or writing tasks
Trouble with open-ended questions on tests
Weak memory skills
Difficulty in adapting skills from one setting to another
Slow work pace
Poor grasp of abstract concepts
Inattention to details or excessive focus on them
Frequent misreading of information
Trouble filling out applications or forms
Easily confused by instructions
Poor organizational skills
"Many people experience some of these signs from time to time and do not have learning disabilities. The time for concern is when a person repeatedly has these troubles that result in a negative effect on everyday life."
Source: National Center for Learning Disabilities online at http://www.ld.org/livingwithld/doihaveld_home.cfm