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You may not have time to play every day with your children, but especially if your family is new to spending time outdoors it will help your kids to know their parents are actively involved. Short hikes, excursions to the local park, and geocaching are all family-friendly activities that help your kids understand that spending time outdoors isn't only healthy, it's fun! If you live in a safe, walkable neighborhood, encourage your kids (and yourself!) to get exercise by walking to places like the library or school. The National Wildlife Federation recommends that you provide a daily "Green Hour" for your children: one hour daily of unstructured outdoor play. Make this time a part of your children's daily schedule. It may not be easy at first, but creating the expectation that your kids will spend one hour every day playing outdoors will help them see it not as a punishment but part of their normal routine.  Be consistent. It may take your children awhile to get used to the idea of living without their cellphones and video games for an hour or two, but be patient and be consistent with them. Engage your kids in conversation about what they did outdoors and ask what they liked best. This will show them that you're interested in their activities (and help you make sure they're staying active and staying safe!). Your children may not want to go outdoors initially, particularly if it hasn't been part of their lifestyle before. You may need to be firm with them in enforcing a "Green Hour," especially at first. Make it clear that this is part of their schedule, and don't give in to complaints.  If your children are reluctant to play outdoors, you could try motivating outdoor play by offering a trade: if they spend an hour playing outside, they can earn some TV or video game time. The more they play outdoors, the more likely they are to discover they actually enjoy it! If the neighborhood is safe for walking or biking, send your kids on an errand. Having a specific goal to achieve may help them get used to spending time outdoors and will give them a feeling of accomplishment. Create challenges. Get your kids outdoors by giving them specific challenges, such as a scavenger hunt or "Survivor"-themed games like a relay race or balance activity. This type of structure will help them figure out how to play outdoors. Adding a reward, such as media time or release from chores, will make your kids even more motivated to head outdoors. If your kids play outdoors, they will probably end up sweaty and dirty, and they need to know that that's okay. In fact, studies suggest that getting dirty can strengthen children's immune systems! Give them some "play clothes" that it's all right to get filthy, and teach them how to clean up after themselves. If your kids have spent more time with a Playstation than a playhouse, they not even be sure of what their options for outdoor entertainment are. Teaching them how to do things like make daisy chains, jump rope, build snow forts, and collect fireflies will help them see the outdoors as full of fun possibilities in every season.  Many nature organizations have websites with lists of activities. You can find a variety of fun ideas just by doing a few quick searches.  You may also want to look for local classes to learn new skills at nature centers, museums, after-school projects, community centers, and more.

Summary:
Model good outdoor behavior. Establish ground rules. Expect some resistance. Accept the mess. Teach your kids things to do outdoors.