Thanks for the reply SaraW, I wish I could advice you on contacting the secondary school. I know "back in the day" when I was young it was not something normally done. But hey, special kids need special considerations. It might actually turn out to be really useful. Good luck with your educational adventures!

Just as a coincidence: I went to school in Groningen and Drenthe, and moved to the USA after graduating college. My teenage years were spent in a rural community - biking 20 km (one-way) to and from school. In elementary school I was quite underchallenged, but a new world opened at Gymnasium. I loved learning languages, and have especially fond memories of my Greek (and Latin) teachers. Feel free to send me a PM if you have questions. Several of my friends in The Netherlands have experience advocating for their gifted (and ADHD) kids. Good luck in your journey! It sounds like you are being quite successful in getting things accomplished for your son!