Here's a clock that Diego and I made a few years ago, when he first started asking me about time:
I made the dots and attached the popsicle sticks for him, and then we did the rest together. I did make a tiny pilot hole before installing the popsicle sticks, and the screw is fairly tight so that the hands can be spun around easily, but still hold their positions. Our clock is mostly used in imaginative ways, with occasional counting and time-learning play.
Made from scrap wood, popsicle sticks, tiny wood screw, felt-tipped pens.