Acid rain is a term used generically to describe any type of acidic moisture, be it rain, snow, or fog. Acid rain can have devastating effects on not only aquatic ecosystems but also terrestrial areas. Acid rain not only affects naturally-occurring surfaces, such as exposed rocky surfaces of mountainous regions, but also human-made surfaces as well. Different stone and metal substances used in the construction of buildings, statues, monuments, etc. may all be affected by acid rain. The rates of erosion and weathering may increase rapidly depending on the degree of acidity in the precipitation. In this activity, students expose many rock materials and metals, both naturally-occurring and common in construction, to an acidic environment and examine the reaction of these materials in contrast to the same materials exposed to “normal” rain (tap water). Kit contains enough materials for 15 groups. Teacher’s Manual and Student Study Guide copymasters are included.