The ability to break a concept into its similar and dissimilar characteristics allows students to understand (and often solve) complex problems by analyzing them in a more simple way. Teachers can either directly present similarities and differences, accompanied by deep discussion and inquiry, or simply ask students to identify similarities and differences on their own. While teacher-directed activities focus on identifying specific items, student directed activities encourage variation and broaden understanding, research shows. Research also notes that graphic forms are a good way to represent similarities and differences.
Four Related Areas:external image images?q=tbn:ANd9GcTus3teL5-MU1UUYI8KPgeDcu023enUJ9_k2bM_JLu0uVfTcKC4CA
  1. Comparing
  2. Classifying
  3. Creating Metaphors
  4. Creating Analogies

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Research Shows:
  • Clear structure is first necessary.
    Students progress into extensive exchange of ideas.
  • Graphic and symbolic representations helps students to understand and utilize processes for similarities and differences identification.
Classroom Practice
  • Teach students to use comparing, classifying, metaphors, and analogies when they identify similarities and differences.
  • Give students a model of the steps for engaging in the process.
  • Use a familiar context to teach the steps.
  • Have students use graphic organizers as a visual tool to represent the similarities and differences.
  • Guide students as they engage in this process.
  • Gradually give less structure and less guidance.
  • Activities Similarities and Differences

Key Research Findings

  • Cognitive research shows that educational programs should challenge students to link, connect, and integrate ideas (Bransford, Brown, & Cocking, 1999).
  • Results of employing these strategies can help to boost student achievement from 31 to 46 percentile points (Stone, 1983; Stahl & Fairbanks, 1986; Ross, 1988).
  • Students benefit by having similarities and differences pointed out by the teacher in an explicit manner. This can include rich discussion and inquiry, but allows students to focus on the relationship or bridge to the new ideas (Chen, Yanowitz & Daehler, 1996; Gholson, Smither, Buhrman, & Duncan, 1997; Newby, Ertmer, & Stepich, 1995; Solomon, 1995).
  • Students also benefit by being asked to construct their own strategies for comparing similarities and differences (Chen, 1996; Flick, 1992; Mason, 1994, 1995; Mason & Sorzio, 1996).
  • Combining this strategy with the method of using nonlinguistic representation enhances student achievement significantly (Chen, 1999; Cole & McLeod, 1999; Glynn & Takahashi, 1998; Lin, 1996).


  1. Students benefit by direct instruction and open-ended experiences in identifying similarities and differences. Teachers can increase learning potential with research-based strategies, such as:
  2. Point out similarities and differences. Present students with similarities and differences explicitly when this helps them reach a learning goal. As a result of the teacher's instruction, students recognize similarities and differences in order to understand something specific.
  3. Allow students to explore similarities and differences on their own. When the learning goal is to engage students in divergent thinking, ask them to identify similarities and differences on their own.
  4. Have students create graphic organizers. Help students to create or use graphic or symbolic representations of similarities and differences, classification systems, comparisons, and analogies. Suggestions include Venn diagrams, comparison tables or charts, hierarchical taxonomies, and linked maps.
  5. Teach students to recognize the different forms. Help students recognize when they are classifying, comparing, or creating analogies or metaphors.
  6. Recognize that All the World's a Stage. Language is rich with metaphor. As students encounter metaphors in reading or speaking, generate a class list. Metaphors provide a source of history, generate literary references, and suggest new ways for students to express ideas.

Asking students to identify similarities and differences in the content they are learning helps them restructure their understanding of that content. During the process, they make new connections, experience fresh insights, and correct misconceptions. These complex reasoning procedures lead students to deeper understanding.

The above information was developed by Northwest Regional Education Laboratory, Portland, Oregon; Title: Nonlinguistic Representation. © 2005 - Focus on Effectiveness is a product of the Northwest Regional Educational Laboratory. These materials are in the public domain and may be reproduced without permission. The following acknowledgment is requested on materials which are reproduced: Developed by the Northwest Regional Educational Laboratory, Portland, Oregon