Do you suspect that your child may need special education services? If your child has not been officially diagnosed, but you have a feeling that they need services, you have the right to request an evaluation for services.
A parent can request a special education evaluation at any time if they believe it is necessary. Interventions and a special education evaluation can be in process simultaneously.
If the school your child goes to is resistant to doing an evaluation (perhaps because they think they need to try an intervention first) you can (gently but firmly) remind them that it is the law. This letter from the U.S. Department of Education might be helpful:
Two other groups that might be helpful:
Student Advocacy Center
In particular, you might appreciate the sections on Special Education.
Ann Arbor has a Parent Advocacy Committee for parents of students with special education issues. In fact, most of our schools have parent representatives. You can find the list of contacts on their web page.
Most importantly, I have found that these parents are fonts of knowledge--if you are worried about your child, they not only often know what you are going through, but can help shorten your learning curve and share important resources.
Just know--you are not alone.