I love it inside Grotto Canyon, I think it's incredibly gorgeous (and shady, depending on what time of day you go!). The rocky footing can be a little trickier for the kids than a plain path, but it's also way more fun for them to climb their way through, jumping their way across the creek over and over again. Who am I kidding? I found it really fun too!
Our best family memories seem to be made when we spend some time outdoors together, and nothing makes the kids feel more accomplished than when they complete a hike. I always make sure to make a big deal of it and point out how proud they feel of themselves and how proud I am of them, building in those positive feelings around outdoor adventures.