Use sunset as your turnaround alarm.
The appeal here is specific: the creek drops through a hole it has worn in the rock, so the falls pour out of what looks like a donut rather than over a lip. It is 8.9 miles up Big Cottonwood to a short gravel spur and a small dirt lot with limited parking. There are two accessible vault toilets at the trailhead, which matters with young kids. The last stretch to the falls is a rock scramble, and wading in the creek is not allowed anywhere in this watershed.
Waterfall that pours through a donut hole in the rock. Kids scramble right up to it.
Water bottle, sunscreen, hat, snacks, comfortable shoes.
Make it a weekend: Spruces Campground (Camping, 1 mi) · Redman Campground (Camping, 3 mi) · Albion Basin Campground (Camping, 5 mi) · Tanners Flat Campground (Camping, 5 mi)
More hikes nearby: Lake Blanche (Hike, 4 mi) · Silver Lake Boardwalk (Hike, 4 mi) · Cecret Lake (Hike, 4 mi) · Lake Mary, Martha & Catherine (Hike, 4 mi)