Compare and Contrast Sources¶

Strategy · All strategies
Evidence · 3 claims (1 for, 1 mixed, 1 against) · 6 studies (3 causal, 3 quant-synthesis), q3–q4 · 2 of 6 report an effect size

Description¶

Present learners with multiple sources on the same topic and have them compare and contrast the information presented, including information conveyed through photographs and other images as well as text. Guiding questions structure the comparison: When was each source created or updated? What is similar or different about the images on each page? What is the main idea or reason behind each page? What seems to be the author's purpose on each page?

Design Implications¶

Comparing multiple sources shifts learners from single-text comprehension to multiple-document literacy — evaluating sourcing, corroboration, and author purpose across texts. Research on multiple-document comprehension shows that learners rarely engage in cross-text comparison spontaneously; explicit task instructions to compare and evaluate sources are needed to produce intertextual processing Multiple-document tasks requiring source evaluation produce deeper intertextual understanding than single-document reading. [+M]. The strategy enacts Cognitive Flexibility by requiring learners to revisit the same content from multiple perspectives, which supports transfer to new cases and guards against overreliance on a single account.

Context¶

Requirements¶

• Multiple sources on the same topic that genuinely differ (in perspective, date, medium, or reliability) — comparison of near-identical sources yields little
• Guiding questions or a comparison organizer (e.g., Venn diagram, sourcing chart) that direct attention to author, purpose, date, and evidence
• Sufficient time; source comparison is slower than single-text reading and should be planned as a multi-session activity
• A synthesis step where learners state which source is more reliable and why, not just list differences

Constraints¶

• Novice readers often treat each document independently and fail to link them without explicit prompts Multiple-document tasks requiring source evaluation produce deeper intertextual understanding than single-document reading. [-M]
• Comparing sources increases cognitive load; learners with weak single-text comprehension may become overloaded before any evaluation occurs Cognitive overload degrades learning. [-S]
• If sources are too similar, or guiding questions focus only on surface features, the activity degrades into spot-the-difference rather than critical evaluation
• Requires background knowledge to judge reliability; learners without domain knowledge may judge plausibility by surface cues [~M]

Implementation Variability¶

• Structured worksheets for novices: a sourcing chart with fixed rows (author, date, purpose, evidence)
• Open comparison for advanced learners: choose their own criteria and justify them
• Media variation: compare a textbook page, a primary-source photograph, and a news article on the same event
• Digital verification variant: extend comparison to evaluating web sources via lateral reading — leaving a page to check who is behind it

Target Learners¶

• Upper elementary through adult learners; elementary students need heavily scaffolded questions and image-based sources
• History and science students, where accounts of the same event or phenomenon legitimately differ
• Learners developing information literacy for web-based research; explicit source-evaluation instruction improves their discrimination of credible sources [+M]

Target Learning Goals¶

• Multiple-document literacy: corroborating, sourcing, and contextualizing across texts Multiple-document tasks requiring source evaluation produce deeper intertextual understanding than single-document reading. [+M]
• Critical evaluation: judging reliability, bias, and author purpose
• Conceptual understanding through contrasting cases — seeing what varies across accounts clarifies what is stable in the underlying concept Erroneous examples build conceptual knowledge. [~M]

Instructions¶

1. Select 2–4 sources on the same topic that differ in perspective, date, or medium; prepare them as Assigned Readings.
2. Have learners read each source individually, Annotating for author, date, purpose, and main claim.
3. Pose the guiding questions (When was each created? What do the images convey? What is each author's purpose?) and have learners record answers in a comparison organizer.
4. Use Class Discussion or Peer Discussion to surface disagreements between sources and candidate explanations for them.
5. Require a synthesis product: a short written or oral judgment of which source is most reliable and why, using evidence from the comparison (Argument Construction).

Related Strategies¶

• Case-Based Learning — multiple sources often constitute the case materials; comparison deepens case analysis
• Analogical Reasoning — comparing two accounts is a structural alignment task, the same mechanism that powers analogical learning
• Combine conflicting-document discussion, declarative source knowledge, and contrasting-case practice to train source evaluation

Related Elements¶

• Assigned Readings — the source set is the raw material
• Case Studies — contrasting cases function as miniature case studies
• Class Discussion — the venue for resolving discrepancies between sources
• Argumentation — the synthesis step is an evidence-based reliability argument

Examples¶

• Stanford History Education Group — "Reading Like a Historian" (sheg.stanford.edu): free lessons presenting two or three conflicting primary documents on events like the Boston Massacre; students source, contextualize, and corroborate before writing a judgment.
• Lateral reading assessments (Wineburg & McGrew): students compare what a web page claims about itself with what other sites say about that page — the comparison is the evaluation.
• Elementary science: comparing a textbook diagram of the water cycle with a photograph of local weather and a news report on drought, using the guiding questions to surface how each medium conveys different information.

Key Sources¶

• Wineburg, S. S. (1991). Historical problem solving: A study of the cognitive processes used in the evaluation of documentary and pictorial evidence. Journal of Educational Psychology, 83(1), 73–87. doi:10.1037/0022-0663.83.1.73
• Spiro, R. J., Feltovich, P. J., Jacobson, M. J., & Coulson, R. L. (1988). Cognitive flexibility theory: Advanced knowledge acquisition in ill-structured domains. Harvard Educational Review (reprinted in Cognitive flexibility theory: Advanced knowledge acquisition in ill-structured domains, Erlbaum).
• Bråten, I., & Strømsø, H. I. (2009). Effects of task instruction and prior knowledge on careful processing of multiple documents. European Journal of Psychology of Education, 24(3), 309–324.
• Wineburg, S., & McGrew, S. (2019). Lateral reading and the nature of expertise: Reading less and learning more when evaluating digital information. Teachers College Record, 121(11), 1–40. doi:10.1177/016146811912101102