GOTTA SEE THE GEYSERS
"Most people don't realize that Yellowstone is actually one big volcano," Laura points out. "There's magma under the surface of the earth—even right beneath our house!" Morning is an ideal time to get an unrushed, intimate look at the park's astounding thermal features.
Start by hiking half a mile from the Old Faithful Visitor Center to Observation Point, which overlooks Yellowstone's most famous attraction and provides a view of the entire geyser basin. Then check in with the rangers at the visitor center to find out when some of the other springs are expected to erupt. Old Faithful goes off every 90 minutes, round the clock—it's the most regular, if not the most dramatic, in the park. The Brown girls' favorite geyser "performances": Beehive (just behind Old Faithful and astonishingly noisy—but erratic) and Riverside (which erupts infrequently, but for up to 20 minutes at a time in a magnificent 75-foot arc over the Firehole River).
Plan to wander in the geyser basin for a couple of hours, browsing among the hissing, bubbling, sulphurous mud pots, fumaroles, and hot springs. As Wendy notes, "There are more here than in the whole rest of the world combined!" Don't miss a swim in the Firehole River, just north of Old Faithful. The Firehole lives up to its name, to a degree; the hot springheated water is pleasantly warm, though not boiling. "There's a short section of rapids where you can just float along," says Laura. "It's so fun—we climb out, run back, and do it over and over again." If you prefer to stay put, find one of the shallow, protected wading spots that are perfect for small children. On your way to or from the river, be sure to check out Fountain Paint Pot, a bubbling mud pool ("like something out of a science fiction movie," says Wendy) surrounded by still more geysers. If you're lucky, you'll catch six blowing at the same time.
HIKES FOR EVERYBODY
The Brown kids actually like hiking—and, as an initiation for others, they recommend the two-mile Bunsen Peak Trail (located near Mammoth Hot Springs and named for the German chemist who invented the Bunsen burner). It climbs 1,300 feet to the summit, which provides a spectacular 360-degree vista of Mammoth and the Tetons (yes, that's Grand Teton National Park next door). "You can go up as far as you want to," says Becca, "and you have good views the whole way."
Point Sublime, near Canyon Village, at the Grand Canyon of the Yellowstone River, delivers an equally awesome panorama—"but keep an eye on the kids," warns Jeff. "The canyon drops off steeply." Tip from Wendy: take along blank postcards (from art-supply stores) and compact watercolor sets or colored pencils. "The canyon-rock colors are incredible—pink, red, orange, yellow. You can set up a studio on a bench or a log and make your own souvenirs."
After the hike, drive through Hayden Valley to Yellowstone Lake, watching for grazing bison as you go. "Be warned that Harry Potter fans will insist on visiting thermal features with names like Sulphur Cauldron, Mud Volcano, and Dragon's Mouth," says Jeff. Stop for lunch, and more lovely vistas, at the sprawling 1891 Lake Yellowstone Hotel (Lake Village; 307/344-7311; lunch for four $30).
While you're there, you can rent a rowboat or take a guided fishing trip down the road at Bridge Bay. "You might catch a cutthroat trout," says Sarah. "That's what the grizzlies eat."
HOW ABOUT A WOLF-WATCH?
On weekends the Browns often hop out of bed at dawn and head for Lamar Valley in hopes of spotting the elusive gray wolf (packs are most active at dawn and dusk). In the decade since Yellowstone's famous wolf reintroduction program began, the population in the park has rebounded to about 118. "Hearing the wolves howl is like nothing you've ever heard in your life," says Becca. Remember to take binoculars. "Jeff brings his high-powered ones, but each of the girls also has her own inexpensive pair, so they don't have to ask every time they want to see something," says Wendy, who buys the binoculars at the Mammoth General Store. "They're durable enough that they can be dropped and won't break. And they're always getting dropped."
Following their weekend wolf-watches, the Browns usually drive over to Cooke City, Montana—the minuscule hamlet outside Yellowstone's northeast entrance—for breakfast at the Soda Butte Lodge (209 Hwy. 212; 800/527-6462 or 406/838-2251; breakfast for four $25), plus a slice of "Joan's blueberry pie." Cooke City resident Joan Humiston's pies often sell out before lunchtime.
TIME FOR A PICNIC
The most foolproof summer activity, Jeff insists, is simply packing a lunch to eat in the wilderness. "You can buy all your ingredients in the morning at the Canyon Lodge Picnic Shop, in Canyon Village, at the center of the park," says Wendy. Then set yourself up by Solfatara Creek, which flows past the Norris campground, or Lava Creek, on the road from Mammoth to Tower Fall. "Spend a few hours simply relaxing and playing in the water," says Jeff. The primary objective: Slow down. "Your kids will remember more of Yellowstone from an unhurried afternoon than they will if they're herded from one sight to the next."