If you suspect he might have inattentive ADHD and you want to try something like stimulant medication (or any type of medication) obviously you need a diagnosis. You can get a good idea of whether he fits the DSM criteria just by looking online. There are parent/teacher rating scales that basically confirm it. Although I recommend taking him to a neuropsych rather than relying on a paper-pencil inventory. If you don't plan to try medication then you could try interventions yourself based on books like "Smart but Scattered" but if you want the school to do interventions for a 504 plan or IEP you would need a diagnosis.
http://www.helpforadd.com/2013/june.htmMy daughter has an IEP for ADHD and I think she would be lost in middle school without that. I would be constantly emailing teachers trying to explain what her issue is and negotiating missing assignments, etc. With the IEP a case manager keeps track of her grades and assignments and deals with her issues. Some kids have 504 plans for ADHD which is just a list of modications/accommodations (like giving increased time to do work or modifying the assignments) but it seems to be really hard to get teachers to follow the plan.
