Surprising and Fun
The Mirlo Blanco Activities Center is a fun option for non-skiers and those with younger children not ready for the slopes. There are a bunch of activities which are a lot of fun (I'm 27 and I laughed like a little kid), especially the sled-rollercoaster. It's called the "Tirineo Ruso" in Spanish, and it's a self-controlled sled on tracks which is drawn to the top of a hill from where riders can whip around the curves at breakneck speeds heading back to the bottom. It was a blast, we must have done it 4 or 5 times.
They also have a slope for "ski-biking," which basically involves riding down a mini ski slope on a bicycle that has skis instead of tires. Again, seems a bit juvenile, but that's not a bad thing. My group was all adults and we couldn’t get enough of it. In winter, they also open a course for tubing and tobogganing down the slope.