Components of a mixture
Soil
4th Grade
Objectives
Science
4.5 C compare and contrast a variety of mixtures and solutions such as rocks in sand, sand in water, or sugar in water
Math
4.13 B interpret bar graphs
Materials
-Student journals/pencils
- Whiteboard or chart paper/markers
-Scrap white paper or paper plates, one per student
-and lenses, one per student
-Hand trowels (optional)
-Clear packing tape (optional)
Engage (indoor or outdoor classroom)
-Review expectations of working in the outdoor classroom.
- Ask students to share with a partner or the whole class what they think they might find in a
Handful of soil.
-Which component do they think they would find the most of in a handful of soil?
Explore (outdoor classroom)
-Bring students to an area where they can each take a handful of soil. Try to get some variety in the type of soil that is collected by allowing the class to spread around the outdoor classroom to gather the sample that they’ll examine.
-Bring students back to a central location where they can begin to look through their soil sample and start a list in their journal of the different things they see. Note: This can be done indoors if weather conditions are not favorable to staying outside.
Explain (indoor or outdoot classroom)
-Ask students to share some of the things they're finding in their soil.
-Introduce or review the term mixture and ask students if they think that the soil they are
looking at is a good example of a mixture. What are the different components of the soil they’re
looking at? Does it contain living and nonliving components?
-Suggest that they try to record their observations by creating a table in their journal and keeping
a running tally of each type of component they find in their soil sample. For example:
Component
Number found total
earthworm //
Roly poly ///
sticks /
rocks ///
Elaborate (indoor classroom)
-After students have had time to collect data on the different components of their soil sample, suggest that the class compare their data with one another. Which type of graph would make it easiest to see which type of component each soil sample had the most of?
-Give students time to translate the data they collected into a bar graph, providing the necessary scaffolding so that graphs are consistent across the class for making authentic comparisons.
-After each student has created a bar graph of the different components of their soil mixtures, lead them in a discussion about why they think certain soils had higher amounts of different components (For example, soil taken from under a tree may have more rocks than soil gathered from a vegetable bed).
Possible extensions:
-Use the compost pile instead of soil.
-Use the data gathered to figure out the fraction/decimal/percentage of each component.
Example: 3 worms out of 60 ingredients = 3/60 = 1/20 = .05 = 5% of the pile.
-Have students add more components to the soil in their garden beds to make a better “mixture”
for the plants (such as compost or organic fertilizer).
Evaluate
-Have students use the same data collection/analysis process with a different mixture.