Charles Baakel
Potato Chip Classification
-Overview/motivation for the lesson
The purpose of this activity is twofold. It introduces the structure and function of a dichotomous
key preparatory to asking students to identify plant and animal specimens. It also reinforces the
idea that there are many "right" answers in science
-Materials
Multiple varying brands of potato chips
Chalkboard or projector for recording the class key
Representative samples of each type of chip in labeled plastic bags (quantity depends on class
size/group size)
Paper and pencil for student group recording
-Goals for the lesson (i.e. what questions should the kids be able to
answer)
Students will be able to:
1.
2.
3.
4.
Classify "specimens" (in this case, potato chips) according to observable characteristics.
Prepare a "key" showing their classification system.
Use their key to identify a specimen.
Recognize the validity of classmates' classification systems
-Vocabulary introduced
classification
organism
specimen
key
-Introduction/how to capture the kids' interest
Start this activity by having students participate in a brainstorming session where they come up
with different ways in which objects or living organisms could be grouped (e.g., size, shape, or
color). Ask students to write down their ideas in their journals.
Then, ask students to think about some common objects they might find around their homes, like
clothes.
Ask questions such as: Could your clothes be divided into different groups (like pants, shirts,
shoes)? If so, how would you divide them?
What about the dishes in your kitchens? How would you group those?
-Demonstrations/activities
1. Display bags of potato chips and discuss their similarities and differences.
2. Ask volunteer to divide chips into two groups using an observable characteristic (i.e.
flavored/not flavored).
3. Record results of first division.
4. Continue to divide groups of chips, using a different characteristic each time, until only
one bag of chips remains in each group. Continue recording results.
5. Using the class key, identify "unknown" chips.
6. Divide class into groups of four to six students.
7. Provide each group with a sample set of chips.
8. Ask each group to devise and test a dichotomous key that is different from the class key.
9. Record and share results.
10. Eat the chips!
-Discussion of results
Explain to students that scientists classify animals depending on the features they share and that
animals can be classified in a number of different ways. For instance, they can be classified by
where they live, by what they eat, and by their body structure.
-Possible Q&A material
Lastly, provide careers that classify like archaeologists, botanists, astrologists, etc.
In addition, to add more fun, possibly look up latin words for the possible types of description,
like flat or salted. We could make up new “names” for the chips.