It is possible to demonstrate the effects of chemical weathering on various rock forms by collecting two samples each of limestone, marble, granite, sandstone and quartz. These rocks may be gathered locally by teachers who recognize their composition or ordered online. Gather 10 cups and place one rock in each. Label the cups with the type of rock and write "tap water" on the label of the first sample and "carbonated water" on the second for each rock type. Add the type of water indicated by the label to each cup and leave for 15 minutes. Record observations and leave in water overnight. Students should notice the carbonated water causes disintegration of the rock more rapidly than tap water. Discuss the reason for this in the context of chemical weathering.
Certain substances are more affected by physical and chemical weathering than others. Elementary teachers should provide samples of plastic, cardboard, leather, cotton and paper. Ask students to hypothesize, in order, the extent to which each material will be affected by weathering respective to the other objects. String clothesline or wire between two trees and attach the experiment subjects to the line with clothespins. Observe the items over a three-week period. Record the changes in each material and discuss why cotton is more resistant to weathering than paper.
Provide each child with 10 sugar cubes, a canning jar with a screw-on lid and two paper plates. Instruct the children to record observations of the sugar cubes' appearance and place in the jar. Put the lid on and shake the jar vigorously 20 times. Remove the lid and dump the contents on a paper plate. Ask students to identify whether the shaking process was an example of chemical or physical weathering and to record the effects on the cubes. Separate the cubes from the crumbs and return to the jar. Shake the jar 20 more times and dump the contents on the second plate. Compare whether more crumbs were created during the first weathering simulation or the second and ask students to provide possible explanations for this.
Certain metals are specifically chosen for outdoor use because of their natural resistance to weathering. Science teachers should place samples of common metals such as aluminum, iron, steel, and copper in a large plastic tub. Simulate naturally occuring weather-related phenomena such as ocean salt spray, acid rain, high winds and sandstorms in the tub over the metal samples using fans, water sprinklers, solutions of salt water and sand piles. Observe and discuss the effects of each weathering process on the metal samples and encourage students to derive conclusions about what metals are best for protecting underground lines, constructing phone and electrical cables, and building patio furniture.