Tell your pediatrician, the doctor he sees for checkups and colds, that you think something was missed. Ask for a referral to a developmental pediatrician and to a neuropsychologist. If you get resistance, push back. Insist. Take your grandson in for an appointment and make sure it is at a time when he will be tired and let the doctor see some of the behaviors. Not a full blown rage, but a difficult time. I often found it was far more effective at getting doctors to do what I wanted. Or else I took in video and made them sit and watch it in my presence. They griped about it, but what did I care that they were not happy? I was paying for there time, I got to tell them what to do in that time. Period. Yes, I can be a bit insistent with them, but only if being nice doesn't work the first 2 or 3 times. Or I am really tired of the bovine excrement being given to me on my child's behalf. Learn to be assertive for your grandson, and teach his mother to be also.
Rquest an IEP in writing. THis puts into place federal protections. Each time they send him home from school is a suspension. They only get 10, or maybe 10 days of suspension. I am not sure if it is days or suspensions. Either way, there is a limit and sending him home early because he is having a fit, well, that counts as 1. If they do it 2 days in a row, but he went to school in the morning? If you send a letter requesting evaluation for an IEP, that puts those protections into place and they only get 10. Then they have to evaluate his placement.
Your son has a legal right to what is called FAPE in LRE. That is a Free and Appropriate Public Education in the Least Restrictive Environment. Maybe he needs an aide. Or occupational therapy to help with sensory integration disorder. This can be a HUGE problem for kids on the autistic spectrum. I will be blunt, your son sounds like he might be. I am just guessing here. SWOT and I often think alike. But my son (now 26, fully self supporting and living in his own apartment) has a very high functioning form of autism that used to be called Aspergers. He has separate diagnoses of ADHD and Obsessive Compulsive Disorder (OCD) (or CDO as he calls it, because then it is in alphabetical order, yes, I do insert an eyeroll there!). He certainly also had ODD, but that is a garbage diagnosis.
ADHD and Obsessive Compulsive Disorder (OCD) are often part of autism spectrum disorder, especially the type my son has. The Obsessive Compulsive Disorder (OCD) includes becoming obsessive on a particular subject. It is part and parcel of Aspergers. My son learned to moderate this in certain social situations because we refused to allow him to only speak about his obsessions. He was high enough functioning that we could insist on this. Many kids are not high enough functioning for their families to make this happen.
Adhd is real. Stimulants really do help. I can see why you would be distrustful. But they don't work like stimulants in someone who truly has adhd. What if the hardest thing you had to do all day was to sit still? You had to do it ALL DAY and you simply were incapable of it? I bet after 3 years you would be pretty angry at those authorities who didn't recognize that you were not trying to be badly behaved. They yelled at you no matter how hard you tried. You got into trouble no matter what, so after a while, you figured you might as well do whatever you wanted, or even do the opposite of what they wanted. This is what a LOT of adhd kids end up doing, esp the boys. My mom is adhd and remembers being so frustrated and upset because no one ever recognized how hard she tried to not follow the 100 things per minute that popped into her head that just HAD to be done RIGHT NOW!!! Instead she got into trouble for not being well behaved like the other girls. She remembers this as early as first grade. If she was really interested in something, like a book, she would focus on it so completely that she would block out thoughts of everything else. Then she didn't hear when she was told to stop reading, or to do something else. So she ended up in trouble for that. She found it incredibly frustrating and difficult.
We put my son on stimulants and my mom was skeptical. She hadn't realized that she had adhd yet. She thought that everyone's mind was like that. We lived out of state and she came to visit us. I let her take my son out to breakfast with his siblings without having given him his medication. I let her cope with all 3 of the kids on her own. Then when they got home (first peaceful coffee I had in months!) I got the younger two busy with something. I quietly said it was time for my oldest son's medications and he ran over to me eagerly. That shocked my mom, that he was eager for medication. Then I had him do something with my mom and I while the other kids were busy. The change shocked her. She thought he would be a zombie. He was NOT. He was calmer, but it was a thoughtful and more intelligent calm. It was clear that he was more comfortable in his own skin when he was medicated. That he liked himself better.
My mom paid a lot of attention to my son's adhd over the next few years. She started to research it. Then with the help of a psychiatrist and some testing, she realized she also has adhd. She takes a small dose of a stimulant when she needs to focus on something like her checkbook or taxes. She cannot understand how she ever got an education without the help they give her. It is like having driven for decades with no glasses when she needed coke bottle thick lenses all that time! That is how she describes it.
I call ODD a garbage can diagnosis for a reason. A diagnosis has two parts. The first is a list of symptoms or description of the problem. The second part is the part that aims you toward the help or the solution, the fix. ODD describes the problem, it tells you what it is. The kids do not react well toward authority, they have little respect toward it. It does not give you ANY clue as to what is causing it. ODD can come about because of bipolar disorder due to problems with brain chemistry. It can come about due to schizophrenia, where the person isn't perceiving reality correctly and is hallucinating or having delusions. It can come about because of autism where the person has no understanding of social rules and does not understand that we give older people respect even when they are being incredibly rude because we see their survival to that age as a real accomplishment. Or it could be because a brain tumor is pressing on part of their brain and causing it to secrete a hormone that is making wacky things happen. We just simply don't have a clue why the person is reacting that way.
This is why the ODD diagnosis is not going to help. YOu can find people who will blather on about it, but they won't blather on about it in a way that will help you or your difficult child.
To get some real help, go to the Special Education section of this forum and look for the form letter to send to your school to start the IEP process. The thread will talk about sending the letter via registered certified mail with return receipt requested. You MUST do this becauae otherwise you cannot prove they got the letter.
Go to the link in the bottom of my signature and read about the Parent Report. Start writing on for your difficult child. Trust me, it will help you communicate with the doctors! It can be an incredibly powerful document, one of the most powerful tools you can find to help your child.
Go to the list of books that we recommend and work your way through them as you can.
The very last thing you should do to help your child? Do something very nice for yourself! Often!! This is very very important!!
Welcome to our forum and please, take only the advice that works for your family and your situation.