Students will learn about physical and chemical weathering.
For each group:
For each student:
Earth’s surface is constantly changing. Over time, rocks can be broken down and moved by the processes of weathering and erosion. Weathering breaks rocks into smaller and smaller pieces. There are two types of weathering—physical and chemical.
Physical weathering is the process that breaks rocks into smaller pieces that have the same composition as the rock they came from. Rocks can be affected by changing temperature. During the day the sun’s energy heats Earth, and during the night the rock surface cools. This process can go on, causing the rock surface to peel or flake. Rocks can be affected by water through frost, freezing, and thawing. Water can find its way into a small crack or hole in the rock. When the water freezes, it expands and then, as it melts, it may move deeper into the rock and refreeze. Eventually the rock may break into pieces. Utah has wide temperature swings during seasons, so there is evidence of this physical weathering not only on rocks, but also on our highways. Tree and plant roots may push into a rock and, as roots grow bigger, rock material is pried loose. Gravity can also pull rocks down a hillside where they collide and break into pieces. Abrasion wears away rocks by solid particles carried by wind or water. All of these forms of physical weathering can be seen in Utah.
Chemical weathering may also alter the size of the rock, but it changes the mineral composition or chemical makeup of the rock as well. This can occur through the dissolving action of water. Water mixes with carbon dioxide to form carbonic acid, which can dissolve some minerals over time. Limestone is especially susceptible to rain/carbonic acid. Oxygen can also mix with iron to form rust, which can change the internal composition of some rock. Mosses and lichens produce acids that weaken the surface of rocks. By altering the minerals of rocks, they break over time. Chemical and physical weathering work together to break rocks apart.
1. Use Science Process and Thinking Skills
2. Manifest Scientific Attitudes and Interests
3. Understand Science Concepts and Principles
Invitation to Learn
Give everyone a lifesaver and ask them to put it in their mouth.
Take a small clear container with a lid. Open the container and put about 8-10 sugar cubes in the container. Begin to shake the container.
What do you think will happen? Over what length of time will you see change? What kind of weathering is this? Open your mouth—what size do you think the lifesaver is in your mouth? If this was like weathering, what might we call it?
The Institute for the Advancement of Research in Education. (2003). Graphic Organizers: A Review of Scientifically Based Research. URL: http://firstname.lastname@example.org
This compilation of 29 research studies about the use and effectiveness of graphic organizers. In using graphic organizers, researchers found that students improved critical thinking skills, retained learning, and had higher test scores when taught to use graphic organizers. These studies were carefully selected by meeting the institute’s criteria for scientifically based research as defined by the No Child Left Behind Act.
Gibson, Helen L. (1998) Cases Studies of an Inquiry-Based Science Programs Impact on Students’ Attitude towards Science and Interest in Science Careers. Paper presented at Annual Meeting of the National Association for Research in Science Teaching. (San Diego, CA)
This presentation explores the relationship between inquiry-based
science programs on students’ attitudes toward science. The article states
that inquiry teaching approach in science helps students to connect
classroom activities with personal experiences. Inquiry requires students
to work with others while asking questions, searching for and selecting
information to answer their own questions. The importance of connecting
a problem to a student’s own background can empower students to
become independent learners.
Lee, O., & Fradd, S.H. (1998). Science for All, Including Students from Non-English- Language Backgrounds. Educational Researcher, 27(4), 12-21.
This article addresses the issue of second-language students needing to have ways of making academic content accessible, meaningful, and relevant. Science learning process through inquiry can benefit secondlanguage students learning through the language of science, such as describing, hypothesizing, reasoning, explaining, predicting, and reflecting. It helps preliterate students understanding through hands-on experiences to provide a foundation for academic learning. Second language students can manipulate materials, make observations, and connect evidences to help them acquire science vocabulary.