It is important that you contact your mental health center and ask about their policy and about the length of their wait list before you schedule your GED test date if you wish to recieve accommodations based on test results. This usually means anyone under 18 years of age can request such an assessment. It will be necessary to demonstrate why the assessment would be necessary. If you have dropped out of school the school system may also insist that you re-enroll before any assessment can be requested. For some school systems it may be easier to obtain an assessment during the summertime.
Schools often have summer clinics for new students who are entering their systems.
The school psychologists and educational specialists are not as overwhelmed by cases to complete at that time and may be able to better meet needs. Again it is important that you contact your local school district or your state learning disabilities or ADHD support group for advocacy assistance. Since you are not a registered school attendee, schools often resist providing such assessment. If you have previous assessment from the school but have dropped out and are within school age ranges for attendence you may be able to request a current update of educational achievement done by the educational assessment expert within the local school. See above for some of the limitations of such requests.