I'm flying to Cuba on Friday and I'm looking for a good kiteboard/-surf spot with a school (don't have my own gear, need to rent!).
Can anyone recommend me a spot/school/shop over there??
Thanks in advance!

I "think" the only shop is in Varadero. It will be very difficult to rent kiteboarding gear in Cuba. There are lots of spot in Cayo Guillermo but no shop. Best thing is to bring your equipments.

Varadero - Go to the end of the peninsula (take a bus) - cross the dunes before Marina Palace hotel.
That's the best spot.
Normally you will find a local there who can teach you kite surfing and/or rent kite/board

So no schools in Cayo Guillermo with rental equipment?

As far as I know there's no such thing as kitesurf gear rental in Cuba. There's however a Russian kite-station on Cayo Guillermo (have no bloody idea how they managed to open one), so you might have some luck renting equipment from them.

anyone have experience with the Russians? lol.

Lol, unfortunately the last time I went there, I wasn't aware of that kite station's existence and since we wanted to avoid the usual (for this time of the year) Cayo Gullermo's crowds - we stayed on the neighboring island of Cayo Coco.

But feel free to check these guys out on FB: https://www.facebook.com/groups/tourophone/

The worst thing that could happen - they'll fill you up with rum and will send you riding butt-naked. So what? You'll get something to post in the "Most sexy kite picture" thread!

I was there at end of November and they were supposedly getting a permit to operate as a school "early next month" They are located in the building at the end of the Cojimar closest to the Iberostar, they had a brand of kites called Faith which I'd never seen before.
Unfortunately one of their guys thought it fine to throw down his tricks (he was pretty admittedly pretty good) right next to the beach oblivious to the presence of others. Made a great first impression