(I'm taking a deep breath and hoping I don't offend anyone...)
I think I have to comment on the soda issue before I can address the ADD/ADHD diagnosis issue. NO soda is good for kids. No matter what the symtoms. EVER.
High Fructose Corn Syrup- no matter what you see from the corn industry, it is not good stuff. WHY? The commercials glaze over why "we" hear it's bad don't they? Here is a list if you're curious: It is digested by the liver instead of the stomach, it is often made from genetically modified corn, it is NOT natural and made through a very weird enzymatic process, it is overly sweet and fools our brains into thinking we need MORE sugar... that is just the tip of the iceberg.
Caffeine- can cause increased blood sugar levels, ringing in ears, high blood pressure, decreased sleep times, insomnia, headaches, possibly cancers, heart and breathing problems, addiction... and again, there is more.
Vanillin/Arificial Flavors- Vanillin is the waste from paper mills and the other stuff? Some of it is code for MSG and the other is who knows what... the FDA won't release it. It's ARTIFICIAL though, which means it's not natural and wasn't originally meant to be consumed. This can cause everything from cancer, to your brain chemistry TOTALLY changing. Scary stuff. And sometimes people just immediately go into respiratory distress with no warning.
Artificial colors- things like Red #40, Yellow #5. These are made from petroleum- which you might know as gasoline. They, also, aren't made to really EAT. But they are in most foods now, so they must be safe right? NOPE. Most countries have now banned these nasty chemicals in their foods. America has not. Both Red #40 and Yellow #5, SPECIFICALLY, are linked with CAUSING or contributing to, or worsening ADD/ADHD. In fact, studies in every country show that taking artificial additives OUT of your kids' diets can actually improve their grades, their attention, and their moods, as well as their health and things like energy and decrease obesity rates.
Diet sodas- contain all of this and more, because they also have ARTIFICIAL sweeteners. Even tiny doses in rats can cause seizures, tumors, cancers.. on and on... and in humans, dizziness and all of the above.
Now a word about diagnosing, since I already have preached :(
Sorry, this is just a subject I am passionate about and have spent many hours researching for my own child.
If you or your teacher thinks your son has a problem, then find a therapist you like. You can have him tested. You can take first steps OTHER than medication to help him. Have problems with getting distracted doing huge worksheets? Cut it up into smaller worksheets or cover the rest of the page with a blank paper, etc. A good teacher will be helping you (and herself) know how he is teachable. She will give you specific testing she has seen help, and tell you what the school has resources for. ALL public schools are required to form an IEP (Individualized Learning Plan) for children.
Allergy testing is a good way to go. There is traditional testing by bloodwork, scratch testing, and then there is Meridian Stress Testing (MSA) testing using something like accupressure. HomeFirst does this and it really got to the bottom of some things for my daughter that traditional testing wasn't showing.
Chiropractic work can help. Practically everything in your body is nerves. Once your spine is balanced and adjusted, you feel and function better. I thought this was woo-woo until I was struggling with a specific pain in my back and just happened to have heartburn at the same time- and chiro fixed both (I didn't mention the heartburn, and she asked- I was floored!!)
Adjusting diet- this was a biggie for us. We are on the Feingold diet, which cuts out all of the additives I mentioned above and cuts out certain foods at first until you see if they are "triggers" that create aggression, lack of attention, etc.
Epsom salt baths can help too- start w/half a tablespoon and work up to 1/4 cup.
And lastly, if you do get a diagnosis, and a second opinion, etc and you come to the conclusion that it is ADHD, don't panic. You don't HAVE to medicate. And if you do medicate, you can go to a compounding pharmacy and have them alter the medication so you get only a PURE medication without a lot of added chemicals, etc. You are part of the team you will work with, and you are his mom above all. My daughter is medicated after much much soul searching and me NOT wanting to. It was only after things got really out of control that I decided to medicate her, and she was BEGGING for help. Our circumstances include a lot more diagnoses than your potential one though too. We started her off on what was literally a drop of medicine and worked up until it was working but not making her a zombie. A good psychiatrist will do that too.
I hope this helps and I didn't come off as too much of a know-it-all. I have TONS of info, hours of research saved on my computer and on actual paper. If you are interested in any of it, or want a list of books to read, etc etc. Just message me and I can give you more info.
Hang in there. It sounds like it's nothing. His grades are great! You should be proud. He's probably just a kid being a daydreaming, creative, little kid- they way they are meant to be :)