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Explosion in rock formation with people running, man diving into water, and woman in water.
Explosion in rock formation with people running, man diving into water, and woman in water. H.A. Thomas & Wylie, c1895.

Using Claim, Evidence, and Reasoning (CER) with Primary Source Analysis

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This post was written by Lesley Anderson, 2021-2022 Albert Einstein Distinguished Educator Fellow at the Library of Congress.

Many STEM educators use the claim, evidence, and reasoning (CER) framework with their students, and this framework becomes even more powerful when students also have the opportunity to wonder. Curiosity is an important part of scientific exploration because it drives inquiry-based discovery. By using CER together with primary source analysis, students can practice constructing arguments from evidence, but they can also pose questions that might lead to further investigation.

This strategy can first be modeled with students using this primary source to practice using claim, evidence, and reasoning as a part of the primary source analysis. Once students have learned how to use this strategy, it can be applied to more content-heavy primary sources that involve a deeper analysis of scientific concepts.

The primary source analysis process aligns with the way that scientific thinking occurs in the real world. Scientists rarely make claims based on evidence without asking important questions to drive the inquiry. Encourage students to bring their own questions into the conversation and, when relevant, conduct additional research to explore their own curiosities.

First, ask students to observe the primary source by looking closely and noticing details for a few minutes. Encourage students to write down each detail they notice on an individual sticky note. Students may make inferences in addition to observations, and that is perfectly fine. Ask students to note details in the image that indicate that it’s a theatrical poster. Using the primary source analysis tool, students can begin sorting their sticky notes into the corresponding categories. Using sticky notes can help students determine the difference between an observation and an inference since they will need to discuss and move sticky notes around as they decide where each should be assigned. As students near the end of the time allotted, ask them to reflect on the image and use evidence to explain their inferences. This is a great opportunity to introduce CER and use this strategy in the middle of the primary source analysis. If students are stumped by the evidence, encourage them to look at their sticky notes in the observe column. Questions may come up at any point through the process and these should be added to the primary source analysis tool as students discuss them.

Questions students may ask:

  • What caused the explosion?
  • Why is the man diving into the water?
  • What year was this theatrical poster created?

Encourage students to think about where they might find information to help answer the questions. Which questions could be answered by looking at the item record? Which questions could be answered by further research and where might students begin to investigate?

Please let us know: How might you use this primary source in your classroom? Do you see other opportunities to combine claim, evidence, reasoning with primary source analysis?

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