To begin, we define "successful hike" not as conquering tall mountains or breaking trail speed records. Rather, we think a successful hike is any that ends with most (or preferably all) participants wanting to do it again soon. The point of hiking for most families or outdoor enthusiasts is to get away from that which has been rearranged by man and enjoy the peace and refreshment that comes from experiencing the natural world. Children are naturally good at experiencing the outdoors in this way if we give them the freedom to do it on their terms.
This might go without saying, but you should not head for a lengthy excursion on your first trip, no matter how promising the guide book makes it sound. We did not even consider going to the bottom of the Grand Canyon without training for it. Consider the trail length (one way if it is not a loop) and also the terrain. A mile on a typical flat trail, even one that is fairly smooth, is roughly the equivalent of two miles on a neighborhood sidewalk. Factor in any elevation gain or rocky sections and you may have to triple the distance equivalent. You should also take altitude into consideration as this has a huge impact on stamina.
If you can find a hike that is short enough but offers a great view at the end it will often keep kids well motivated. Who among us has not willed ourselves to keep moving in order to "win the prize?" It is also helpful if you allow the kids themselves to choose the trail, with some guidance about distance, difficulty, etc. As an alternative, trails that offer good wildlife viewing opportunities are almost always a hit with kids. Carry binoculars and be aware of how to view animals safely.
Let your kids stop as often as they wish. If ever there were a good time to be focused on the journey over the destination, it would be this. While this may sound contradictory to tip #2, the point is this: kids will be more cooperative if they have the freedom to investigate the small things that capture their attention. If a trail guide says to plan for 3 hours, know that recommendation is aimed at the average experienced and fit adult hiker and it will take you longer with kids. We always figure on moving at about 1 to 1.5 miles per hour.
Giving each child their own small daypack to carry pays off for everyone. First, it lightens your load as even very young children are capable of carrying a small water bottle or hydration kit plus snacks. Toss in nature study tools (magnifying glass, notebook or sketchbook, field guides) for added incentive to explore and learn. Hiking is also a great way to learn how to use a compass, way-finding skills, and to read a topographic map, and these are the basic wilderness safety skills that everyone who hikes should have at a bare minimum.
We have found that if we pack our kids' favorite snacks they have something to look forward to at some point along the trail. A snack and plenty of water is essential anyway, why not make it fun and exciting. Moms, this is not the time to insist upon some super healthy, organic nutritional superfood, unless your kids have already developed a taste for them. I find most of those things are not much tastier than a shag carpet smoothie and they are expensive. Fresh fruit, veggie sticks, fig bars, even Cheerios necklaces will go over much better and pack just as much of an energy boost. Pack plenty and snack often. Happy tummies cut the complaining.
To pass the time we often play the Alphabet Game. You know, the one where everyone has to work their way through the alphabet coming up with an object beginning with each letter. We have all sorts of variations: national parks, foods, geology terms, animals. The sky is the limit here. Make up your own games or ask thought-provoking questions. Who can name the most different species of wild flowers? If you were a tree, what kind would you be? What are you going to tell your friends about this hike? And don't forget to take the silly pictures.
In addition to your own family's enjoyment, your other goal should be to help maintain a positive experience for other hikers. This means teaching your kids some basic trail etiquette. Use your indoor voice, even though you are outside. Yelling should be reserved for scaring off bears or helping someone locate you should you become lost. If you are going to give your kids safety whistles they need to know they are only for use IN AN EMERGENCY. Blowing them randomly creates a "cry wolf" effect and is pretty annoying to others. Additionally, being quiet means you are more likely to hear birds and glimpse other skittish creatures. Make a game of it by encouraging your kids to listen for sounds they won't hear in suburbia: wind in the trees, a mountain creek, a waterfall in the distance. Click here for a more complete explanation of the Leave No Trace wilderness etiquette.
Allowing children to document the trip their way can yield some great photo memories. You may even want to get everyone their own disposable camera. Search the web for tips on landscape photography (or click here to see mine) and make a learning event out of the documentation. Who knows? You might find one of your kids has a great eye.
I can't stress this one strongly enough. Mountain weather can change in a flash. Above the tree line is last place you want to be trapped in a thunderstorm. You also don't want to get part way into a hike and find yourself slogging through snow or mud that you are not dressed to manage. Check at the ranger station, look up the forecast on a reliable web source, and even if conditions look perfect pack rain gear and a change of dry clothing. You may only be planning a two-hour excursion but you cannot control the weather. Many hiker's days have ended badly when they set out on a day hike and got stuck in the woods for much longer by bad weather.
Even if you prepare well, you might find a hike more strenuous than expected or someone might not be feeling their best. Give yourselves permission to bail out. For this reason, until your family has developed the stamina for longer hikes, choose a trail that is an "out and back" (straight route to destination) rather than a loop. On an "Out and Back" you can turn around at any point to cut mileage but on a loop or 'lollipop loop' you might be stuck going further than is manageable.
This is by no means an exhaustive list of trail and wilderness safety. While I do not believe parents should fear taking kids into the wilderness, there is plenty that can go wrong, even fairly close to well-populated areas and the best way to have a successful outing is to be fully knowledgeable and prepared. Indeed, you are far more likely to be harmed in a city than out in the woods. But remember, YOU are responsible for your safety in the natural world.
For more safety and wilderness etiquette tips visit the National Park Service website or Leave No Trace.