Classification Card Sorting

Materials: ★★☆ Available in most school laboratories or specialist stores
Difficulty: ★☆☆ Can be easily done by most teenagers
Safety: ★☆☆ Minimal safety procedures required

Categories: Classification

Alternative titles: Kingdoms and Domains Intro Activity

Summary

Students use a set of organism cards, representing all five kingdoms and the three domains, to explore how organisms are classified. The activity sparks discussion about differences between classification systems, challenges in distinguishing groups, and why the three-domain system is more widely used today.

Procedure

Provide each group of students with a set of 20 organism cards (pictures with species names).
Ask students to sort the cards into groups they think make sense. Encourage them to explain their reasoning.
Introduce the five kingdoms system and have students re-sort the organisms into: animals, plants, fungi, protoctists, and prokaryotes.
Point out the limitations of this system, particularly with prokaryotes.
Guide students to separate prokaryotes into archaebacteria and eubacteria, using the hint that archaebacteria often live in extreme environments.
Explain the three domains system (Archaea, Bacteria, Eukarya) and have students classify organisms accordingly.
Conclude with a discussion about why scientists prefer the three domains model today.

Links

📄 Classification Card Sort - tes: https://www.tes.com/en-au/teaching-resource/classification-card-sort-11472838

Variations

Add cards for viruses to discuss whether they should be classified as living or non-living.
Challenge students to design their own classification systems and compare them with accepted models.
Provide short fact cards (habitat, cell type, reproduction) to support sorting.

Safety Precautions

If extended with live cultures or specimens, follow microbiology safety protocols.

Questions to Consider

Why do scientists classify organisms? (To organize biodiversity and understand relationships.)
What are the main differences between the five kingdoms and three domains systems? (The five kingdoms group all prokaryotes together, while the three domains separate archaea and bacteria.)
How can we distinguish archaebacteria from eubacteria? (Archaebacteria often live in extreme environments; they also differ in genetics and cell membrane composition.)
Why is classification sometimes controversial? (New discoveries, genetic data, and differing criteria can lead to disagreements.)
Why is the three domains system more widely accepted today? (It better reflects evolutionary relationships based on genetic evidence.)