Your concept is very good, the fire service preachs to children and their parents to have a special meeting place in the event of a fire. In your example, a swing out on the tree is a great landmark for the family to key into in the event that they need to evacuate and re-group in a safe place.
Good concept. Just a thought if you were thinking of the picture as an educational tool: what about a white border around the picture (with a thinner black border possibly) with the "Got a Plan" tagline below, with maybe a question in smaller type below "when this happens to you, do you know what to do?".