IDENTIFYING SIMILARITIES AND DIFFERENCES

 By: Dr. Armãndo R. Tolliver | EDUCATOR | January 30, 2017
            Ever get sick and wonder, “What in the world is wrong with me?” When this happens, we usually turn to the Internet that provides descriptions of the characteristics of various illnesses. These characteristics are grouped by similarities. We then try to classify the illness by finding the category of the illness that the symptoms most resemble. This process involves being able to identify similarities and differences between two or more phenomena, which is often the basis new discoveries. Sciences classes use this type of comparative analysis frequently to examine data, objects, diagrams, models or specific concepts (e.g. prokaryotic vs. eukaryotic organisms, photosynthesis vs. respiration, mitosis vs. meiosis, etc.).

            Identifying similarities and differences is also a powerful instructional strategy, which Marzano, Pickering, and Pollock (2006) described as the “core” of all learning. They went on to say, “It enhances students’ understanding of and ability to use knowledge” (p.155). Because this instructional skill includes the engagement of some mental processing beyond recalling or reproducing a response it is also representative of both Webb’s Depth of Knowledge and Costa’s Level 2. This skill allows students to process and analyze as they identify common and dissimilar characteristics. Keywords that generally distinguish a Level 2 item include “classify,” “organize,” ”estimate,” “make observations,” “collect and display data,” and “compare data.” These actions imply more than one step. For example, when I have asked students to compare data, it first required them to identify characteristics of the objects or phenomenon and then group or order the objects. Level 2 activities include making observations and collecting data; classifying, organizing, and comparing data; and organizing and displaying data in tables, graphs, and charts. 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 (Marzano et al., 2006).

In the classroom, 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. For example, I have given students actual objects, diagrams, and models to observe and interpret. This variation is more kinesthetic and allowed students to actually practice recording quantitative and qualitative observations and inferences. In contrast, I have also asked students to simply think, reflect, and compare various concepts learning during a particular unit of study. While teacher-directed activities focus on identifying specific items, student-directed activities encourage variation and broaden understanding (Marzano et al., 2006; Varlas, 2002). Research also notes that graphic forms are a good way to represent similarities and differences (Marzano et al., 2006). A Venn diagram continues to be one of the most popular graphic organizers used to help students identify similarities and differences, but beyond the graphic organizer, there are also several other activities that encourage this level of thinking. Using a variety of organizers can help to provide differentiation to ensure the success of all students working with all content.

During a lesson about prokaryotic and eukaryotic cells, I distributed a plant, animal, or bacteria cell model to each student. I had students complete a 5-minute quickwrite in which they wrote qualitative and quantitative observations in order to describe in detail all of the characteristics of the model, inclusive of a sketch. Next, students were instructed to find a partner who had an alternate model. The students switched papers and read the other partner’s quickwrite, before editing and adding any new information to their partner’s quickwrite. Then, the partners discussed the edits and addition of any new information. They repeated this step, to also account for all three models. Afterwards, the partners used a triple Venn diagram to examine the similarities and differences of the plant, animal, and bacteria cell models. Students listed the characteristics that are unique to each model in the circle that represents only the model it described. The similarities between each of the models were written in the center where the circles overlap. After students completed the Venn diagram, they analyzed similarities and differences to in order to write summary statements to demonstrate clear understanding of the relationships that existed between the models being compared.

To help students express how the objects compare, I provided the students with a few prompts: a) what categories of characteristics or attributes were used to compare and contrast these models, b) what are the most important qualities or attributes that made them different, c) what can we conclude about these models, and d) what did you learn by comparing these models. For homework, students synthesized similarities and differences in order to create their choice of a diamante poem or a one-pager. The diamante poem is a style of poetry that required students to create a product using the similarities and differences identified in the Venn diagram. The one-pager is a creative way that allowed students to respond imaginatively while being brief and concise in making connections. The students shared their homework assignments electronically with the class. This allowed students to review concepts discussed in the unit multiple times.

Though this lesson went well and allowed students to formulate and revise scientific explanations using evidence, it might be useful to differentiate the lesson by providing students who struggle with a comparison matrix to determine the essential characteristics of concepts.

Suggested Citation

Tolliver, A. R. (2017). Identifying Similarities and Differences. [Education Project Online]. Retrieved online at http://www.educationprojectonline.com/2017/01/identifying-similarities-and-differences.html.

References

Marzano, R. J., Pickering. D. J, & Pollock, J. E. (2006). Classroom instruction that works: Research-based strategies for increasing student achievement. Alexandria,

VA: ASCD.

Varlas, L. (2002). Getting acquainted with the essential nine. Alexandria, VA: ASCD

Curriculum Update.