NSTA Press publishes high-quality resources for science educators. This series features just a few of the books recently released. The following excerpt is from Bringing Outdoor Science In: Thrifty Classroom Lessons, by Steve Rich, edited for publication here. Download the full text of this chapter. NSTA Press publications are available online through the NSTA Science Store.
Rocks and Soils
Humans have built their homes upon the land, often using the rocks and stones from the land as building materials. Rocks and soil are indeed a part of everyday life and an important component of a complete science curriculum.
Where do teachers get rocks to show students? Often a rock collection is one of the more common materials purchased by schools for science teaching. However, not all schools have rock collections, and some cannot afford them. A thrifty science teacher can teach a unit on rocks with only those that can be found in the area. Although some locations may not yield all of the samples that would create a substantial rock collection, there are likely to be enough to share the basic concepts that students need in the elementary and middle grades. The same would be true for soils. Even if there is only one soil type in the area, it can be used as a great starting place for teaching about soils. Local soil can be compared with purchased soil samples (e.g., potting soil or play sand). In fact, it is that comparison that lends itself to great science explorations for young people—comparing both soils and rocks through close observation and hands-on experiences.
Use these resources and the lessons in this chapter to introduce students to rocks and soils in their local area and beyond. Consult your district science curriculum and state science standards to see where these lesson ideas fit best, and consider bringing in a guest speaker from a college geology department, a museum, or a rock and mineral society.
Although these lessons do not constitute an entire unit on rocks and soils, together they do offer an introduction to the important components of the Earth that students see around them every day. Perhaps students will find out why teachers often say, “Science rocks!”
- Jump Into Science: Rocks and Minerals by Steve Tomecek (National Geographic Children’s Books, 2010)
- Rocks, Fossils and Arrowheads (Take Along Guides) by Laura Evert (Cooper Square Publishing, 2001)
- Rocks in His Head by Carol Otis Hurst (Greenwillow Books, 2001)
- Use care when students are asked to use sharp objects (such as those in dissection kits, toothpicks, pipe cleaners, straight pins, rocks, or arrowheads);
- When gathering any objects outdoors (rocks, soil, insects, etc.), it is best to look for locations that have not been sprayed with pesticides, herbicides, or other chemicals; and
- When working with water indoors, completely clean up any spills.
Soils From Here and There
Students will compare and contrast soils from various locations.
Why/How to Use This Lesson
Whether students have lived in one place all of their lives or have moved often, it is likely that they do not think about how soil might be different from one place to another. This lesson will require students to think about the differences in soils from various locations.
Small containers, samples of various types of soil, hand lens, paper plates, and student worksheet (available here)
Procedures and Tips
- In your own travels or in those of friends and colleagues, collect soil samples as a “souvenir” from as many places as you can get them. You might ask a pharmacy for small medicine bottles, or find similar-size containers for collecting soil. Small re-sealable plastic bags will work, too. Once you have several soil samples, arrange them in groups so that you have two or three per set that look as different as possible. Label them with letters, and make a key to indicate where they came from (e.g., A = Miami Beach, B = Mount Saint Helens, C = Great Smoky Mountains, Tennessee). Always include a sample of local soil, too.
- Start your lesson by asking students if soil is the same everywhere. Ask them if they have been anywhere where the soil is noticeably different from the soil near their home. If you live in a strictly urban area, it’s possible that students have not seen the natural soil in the area. (Of course this is possible anywhere, depending on how much experience students have being outdoors both at home and at school.)
- Give two or three soil samples to small groups of students, and ask them to fold the student worksheet and then answer the questions on the top half of the worksheet. Give them time to discuss with other group members where they think the soils originated.
- Give students a key that tells where the soils came from. Ask students to compare the original locations of the soils (as shown on the key) with their predictions and complete the bottom half of their worksheets.
For primary grades, simplify by using just two soil samples. Consider using sand and a dark soil. Primary-grade students can usually identify that sand is the type of soil on a beach or in the desert.
Students should be assessed based on their reasoning regarding where the soil came from, not on accuracy of a specific location where the soil originated. After this lesson, you may wish to ask students to bring back soils from places they visit, perhaps from a grandparent’s home or somewhere they visit during school holidays.
Sample Discussion Questions
- Describe the appearance of the soil in the local area.
- Have you ever been anywhere where the soil looked different? Where? Why do you think some soils have different colors than others?