Magnetic paint isn't...very

To get ready for the holidays, I've been assembling gift sets in my Etsy shopMy goal is to package several smaller items together, creating a more impressive gift. One of my ideas is to feature magnet boards with magnets in some of the sets.
I love old schoolbooks, so I created a set of magnets with images from a 1970s kids dictionary illustrated with fun cartoons. I attached the images to large ceramic dominos, covered the front with clear dimensional glaze, and then glued an extra-strength NEO magnet to the back.
Domino magnets
For the board itself, I thought I found the perfect material when a neighbor gave me an old rack for wooden puzzles. The thick wooden sides would make perfect magnet boards. Or so I thought. 
Boards from a puzzle rack
Other bloggers have written about using magnetic paint -- it seemed so simple! I bought a $20 can (spendy!) and coated the front of each board.
Magnetic paint
It's really more of a primer. After the recommended 3 coats, I covered the boards with another special-purpose paint. Why not make the magnet board double as a chalkboard? I had two cans of chalkboard paint -- one red and one black.
Chalkboard paint
The project took several days, thanks to our cool rainy weather. I was excited to give the boards a try once they were dry.

But alas, my dreams were dashed when I put the first domino magnet on a board. The magnet stayed put UNTIL I gently shook the board. Then it shimmied and slid off. I tried putting a piece of paper under the magnet, but it didn't hold. 

Did I mention that these were EXTRA STRONG magnets? It turns out that the magnetic paint isn't. Magnetic, this is. Not very, anyhow.  I'll have to turn to plan B -- starting with a metal surface and painting over that. What happened to all those cookie tins I exiled to the garage?