What is the role of evidence in a scientific argument?

Introductory Module Session 1

Session Goals:

Two children at a desk are working together
  • Teachers will be introduced to four areas of argumentation in which students need extra support: 1) Evidence, 2) Reasoning, 3) Student Interaction and 4) Competing Claims.
  • Teachers will develop an understanding of argumentation as a social process in which students build, question and critique claims using evidence and reasoning.
  • Teachers will be introduced to a Card Sort as an instructional activity that encourages students to think about what evidence does and does not support a claim.
  • Teachers will design a new lesson or revise an existing lesson to integrate argumentation into their science instruction.*
  • Teachers will identify areas of argumentation that are challenging for their students.* 

*Note: These final two goals are only applicable if the module is implemented as multiple sessions

Session Slides:

Introductory Module Session 1 PDF


  1. Video: Introduction to module
  2. Activity: Mystery card sort 1
  3. Video & Discussion: Encouraging talk about evidence
  4. Session takeaways

​*Extension – Try it with your students!

1. Video: Introduction to module

Watch the video below, which discusses the four areas of argumentation that students need extra support.

2. Activity: Mystery card sort 1

Measuring a tooth that is 5 centimeters

The task: 

  1. Work in pairs or small groups to sort cards as supporting, maybe supporting, or not supporting the claim: The fossil tooth came from a prehistoric mountain lion, which is related to mountain lions that live today.
  2. Make sure to articulate why you sort cards as you do.

Setting up your cards:

Chart - Claim: The mountain tooth came from a prehistoric lion.

Discussion about card sort:

  • What did you talk about when you were discussing the evidence?
  • What types of questions did you ask?
  • How can you envision your students engaging in this activity? What would work well? What challenges might they have?​

3. Video & Discussion: Encouraging talk about evidence

Watch the video below, which describes ways to support student discussions around evidence. 

Discussion Questions:

  • How do the card sort and other types of activities encourage students to talk to each other and develop their ideas?
  • How can students use evidence not only to support claims but also to question and build on the ideas of their peers?

4. Session takeaways

Three students having a discussion at a table
  • Evidence is observations or data about the natural world that is used to support claims.
  • Evidence can be used in different ways, and we use our understanding of science concepts (reasoning) to make sense of that evidence.
  • Some pieces of evidence can be stronger than others in support of a claim.
  • ​Encouraging talk about evidence supports students in thinking critically and building understandings of the science concepts.

*Extension – Try it with your students!

The task:

  • Develop or revise a lesson to encourage students to talk about evidence. This lesson could be a card sort or it could be another type of activity, such as making sense of data from investigation.
  • For the next meeting, bring the lesson you developed, as well as potentially student artifacts (such as writing, or a video clip) of students engaged in this.

View Other Sessions

Introductory Module Agenda

Session NameDescriptionLength
Session #1: What is the role of evidence in a scientific argument?This session introduces the four areas of argumentation that students need extra support in, and then focuses specifically on the role of evidence.45 minutes
Session #2: How does considering competing claims support students’ use of evidence and reasoning?This session illustrates how engaging students in competing claims supports their use of evidence and reasoning, and also deepens their understanding of the science content.45 minutes
Session #3: What is the role of reasoning in a scientific argument? This session focuses on the role of reasoning, and introduces an instructional strategy that can help students incorporate reasoning into their written arguments.45 minutes
Session #4: How do we support students in interacting with peers during argumentation?This session highlights the interactive nature of argumentation using an activity in which students analyze data with peers.45 minutes