In the style of Jules Verne’s book Journey to the Center of the Earth, take your students on a walk, using sidewalk chalk to mark the boundaries between the different layers inside our planet. After you pass through each layer, tell your students about the layer of the Earth they just traveled through. This lesson was developed by Eric Muller of the Exploratorium Teachers’ Institute. Here you will find a student handout for taking notes during the walk, a teacher cheat sheet and some assessment ideas. Download a detailed lesson plan for this activity from Eric Muller’s website, originally published in The Science Teacher, September 1995.