You can ski flat or steep in Grand Teton; the two things to watch out for are hypothermia and avalanches. As with climbing, know your limitations, and make sure you're properly equipped. Check with local rangers and guides for trails that match your ability. Among your options is the relatively easy Jenny Lake Trail, starting at the Taggart Lake Parking Area, about 8 miles of flat and scenic trail that follows Cottonwood Creek. A more difficult ski is the Taggart Lake-Beaver Creek Loop, a 3-mile route that has some steep and icy pitches coming back. About 4 miles of the Moose-Wilson Road -- the back way to Teton Village from Moose -- is unplowed in the winter and is an easy trip through the woods. You can climb the windy unplowed road to the top of Signal Mountain -- you might encounter snowmobiles -- and have some fun skiing down. There is an easy ski trail from the Colter Bay Ranger Station area to Heron Pond -- about 2 1/2 miles, with a great view of the Tetons and Jackson Lake. Get a ski trail map from the visitor centers.
Skiers who come to Jackson Hole are usually after the hard, steep stuff at the Jackson Hole Mountain Resort, but there's a growing contingent of backcountry telemark skiers who ski the Teton Pass area outside of the ski resort boundaries.
