People probably hear tens of claims being made everyday whether in commercials or in conversations. It is important for them to be able to critically analyze the claims so as to not fall prey to misleading and potentially harmful claims. Part of this analysis is to understand the logic, supported by the evidence, used in the claim. I think these analytical skills are needed more than ever as we hear a multitude of unsubstantiated claims being made daily about almost anything.
Students were involved in an experiment that was essentially based on the chromatographic properties of various marker dyes and inks. Students were asked to write a claim for how they thought the different inks and dyes blotted on a paper towel would migrate as water slowly wet the paper towel. The students recorded what they observed in the experiment ( some inks or dyes migrated and others did not). They were then asked to record a possible explanation for what they observed in the experiment.
The ability of students to connect the experimental evidence in a logical way that supported their claim rarely occurred. Part of this may be that they did not have the background knowledge to allow them to make the connections to support the claim. Another reason is that there are few opportunities for students to develop these skills. Regardless, I find that students generally have difficulty in making solid claims based on valid, logical arguments using supporting evidence. Though it seems that there is now a greater emphasis in education to provide students with a wide variety of opportunities to practice this valuable skill.