Rock cycle projects help children to understand how rocks are formed and broken down.
The rock cycle is a popular topic in sixth-grade earth science. The rock cycle describes the way Earth's internal and external processes are responsible for the formation and alteration of different types of rocks: igneous, sedimentary and metamorphic. Before embarking on any rock cycle projects, make sure your students can identify the three types of rocks, and review the way rocks are formed and broken down. This will provide a background that students can build on in their project.
Rock Hunt
Send students on a rock hunt in their own neighborhoods. Students should search for examples of each type of rock in their yards, or in playgrounds and parks near their homes. Show students examples of each type of rock, and discuss where they are most likely to be found. Discuss with the students the geology of their local areas, and ask them to predict what types of rocks they will be most likely to find. Have the students bring in their findings and tally up how many of each type of rock were found. Discuss whether this tally matches the predictions they made.
Rock Life Story
Have students write a short story about the life of a rock. They should describe at least three changes that the rock goes through over time. Remind students that rocks don't only go from igneous to sedimentary to metamorphic -- a sedimentary rock can turn into another sedimentary rock and a metamorphic rock can become a sedimentary rock, and so on. Encourage students to be creative, and to include the "feelings" and "thoughts" of the rock. Instead of a story, students could write a diary or draw a cartoon.
Sediment in a Bottle
Use clean, plastic soda bottles. Students add pebbles, sand, clay and soil to the bottle in layers. Add about two tablespoons of Epsom salt to each bottle, mixed among the layers. Students can also add "fossils" in the form of twigs or shells. Fill the bottles about 3/4 full. Students then give the bottles a shake and cover the layers with water. Keep the caps off the bottles and allow the water to evaporate over time. Leave the bottles in a sunny spot if possible. Once the water has evaporated and the materials in the bottle have dried out, cut away the plastic bottle to reveal the "sedimentary rock."
Rock Fudge
Assign each student a role: Erosion, Uplift, Time, Water, Weathering, Heat, Pressure, Plate Tectonics. Erosion adds 1/3 cup evaporated milk (silt) to a bowl; Uplift adds 1 cup of sugar (quartz); Time adds 1 tbsp. of margarine (organic sediments). Plate Tectonics mixes up the ingredients with a spoon. Heat places the bowl in a microwave oven for 45 seconds. Pressure stirs the bowl. Repeat this three times. Weathering then adds 1 cup mini-marshmallows (limestone) to the bowl, Heat adds 3/4 cup semisweet chocolate chips (basalt), and Pressure adds 1/2 teaspoon vanilla (crude oil). Time and Water take turns stirring the sediments, then Erosion holds the bowl while Plate Tectonics scrapes the fudge (magma) onto the Earth's surface (wax paper). Once it has cooled, students can take the fudge home.
Tags: sedimentary rock, each type, each type rock, Plate Tectonics, rock cycle, type rock, types rocks
