Building a case

After students have explored the domain and scenario well enough that they think they can suggest a solution for their clients, they need to select a claim and support it.

In Volcano, when students click the ``Talk to mayor'' button, they see the screen as seen in Figure 2.13.

  

Figure 2.13: Four major parts of Volcano's report-building screen: Claim selector, working notebook, supporting evidence, and the submit button.

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The distinguishing interface parts of the case-building task are strongly related to the task students have: selecting claims, examining their notebook, dragging over supporting evidence, and submitting the argument. These interface parts are:

• Claim selector: Students need some way to say what they believe about this scenario. In Volcano, students check the box next to the claim they believe. A claim is just a sentence describing a falsifiable statement about the world, and in Volcano they are exclusive--you can only believe one at a time.

• Working notebook: As mentioned above, along the way, students have collected factual points about the volcano garnered from their tests. Although the points have just appeared sequentially in this notebook along the way, on this screen they are able to be dragged from the notebook into the supporting evidence list described below.

• Supporting evidence: Students drag evidence points one by one from their notebook into this list, where they are copied. The idea is that students will drag in those test results that confirm the claim they selected, and only those. Evidence that implies the opposite of the claim is left in the student's experimental notebook. If a student revises which claim they believe, they can drag points that disagree with this new claim to the trash can and bring in different evidence.

Once the student has selected a claim and dragged in all the evidence they have in their notebook that they believe supports that claim, they press the ``Submit argument'' button. This means they believe they have made a well-supported case for the clients to consider. This will get them remediation from the mayor and their co-worker Chris Baker.