Good afternoon, The nest you describe is a killdeer nest. The eggs will hatch after 24 to 26 days of incubation. I hesitate to recommend putting up a barrier because that will likely attract predators to the nest. The killdeer's nesting success depends on its being so well camouflaged among the rocks. Of course, getting accidentally stepped on isn't good for eggs either. Depending on how old the children are, you might consider putting up a small wire flag several feet away from the nest to remind the kids where the nest is located. Please let me know if you have more questions.