A few of us went volcano boarding a few years ago, and even if had just gone for the hike and views, it would have been spectacular. Boarding itself was great fun, but make sure you cover up as much skin as you can and bring water!
Just amazing. Climb is moderate. You must bring your own equipment, but nothing really hard.
Hike up th Volcano wasn't that hard at all. A little tough due to the first quarter being lose rocks, but after that it's a gentle slope up to the sledding point. I'd advise for people to stop as they go to take photos. Very beautiful views. The sledding down as fun but me being clumsy kept going side to side. Lots of fun and would recommend.
Volcano boarding is of course the main reason people come and I did it too but volcano itself is much more attractive than volcano boarding. Hiking up isn't hard even with the board. On the top, the view is amazing and you can feel the heat if you touch the surface. Try to dig just a little bit. You can see steam coming out of it.
I went Volcano Boarding here with Bigfoot (hostel) and it was a blast! Definitely the most fun experience I had in Nicaragua. The hike up Cerro Negro is tough in the high heat and high winds (I'd recommend a porter for your board), but the views and slide down were well worth the trip up.