Challenging what we see

Greetings! I hope you're all having lovely science time in the last term of the year. I've been busy visiting schools sharing ideas about the science capabilities and the Nature of Science.

I came across this lovely image on facebook, the source of all knowledge and wisdom... other than Wikipedia of course... I've seen similar from the "Fake Science" folk (like the Rex wielding shovel) so I'm thinking it's the same folk.
  

I do like these because they quite nicely reflect the first capability about Gathering and Interpreting Data as well as leading nicely onto the second one Using Evidence. Both posters are based on direct observation (the gathering of data) -paleontologists have dug into the ground and found the bones of dinosaurs. Both posters seem to have an explanation for what the scientists have found and here's an easy way to show the difference between an explanation and an inference -if these are explanations then we need to see evidence of the statements. We would need to perhaps find a shovel or claw marks as dinosaurs have dug into the ground looking for something to eat. The first one is more interesting because it would be pretty hard to find evidence that this is true. However we have found evidence to disprove this and I like the idea of getting children not to just prove an explanation but to also disprove them. We have fossil evidence of tissues and skin samples. One of the best is a hadrosaur (http://news.nationalgeographic.com/news/2007/12/071203-dino-mummy.html) so this shows that at least some dinosaurs had skin and internal organs, etc.
Without the evidence, these statements are just inferences based on the "scientist's" observations. We do want to encourage our children to not just collect data, whether it be statistical results from a glider flight, noticings from an object or a video, or measurements from a chemical reaction experiment, but to interpret it -are there patterns in the data?, can you start making assumptions or inferences?, can you surmise that perhaps the spider is doing a courtship dance or waving off a predator by making itself look bigger (https://www.youtube.com/watch?v=d_yYC5r8xMI)? As we use science knowledge or prioir knowledge, we will be inferring... to turn this into an explanation we may need to investigate further, perhaps carry out the experiment again, or plan a new investigation to seek some answers, or watch some more videos of peacock spiders. As we gather direct evidence or proof, we can start creating our explanation!

The explanations students make may still be wrong, and challenging their thinking and results is all part of the fourth capability Critiquing Evidence: are you sure that what you have decided is the explanation based on this evidence is correct? Could the results be actually showing something quite different? I use the good ol' cellophane fish experiment for this... I put the fish on a child's hand and it should wriggle around. Then we put it in another child's hand where it will again wriggle but may behave a little differently. Children are noticing excitedly and already starting to infer that it may be heat, contact with their skin, etc... These are all inferences until they try to find data... If it's heat, will it work on a hot surface? They usually put the fish on a cold table surface and nothing happens -then a sneaky facilitator suggests breathing on the table to "heat it up" and the fish wriggles confirming their theory. Actually the fish is wriggling because of moisture on the surface it's on -children need to get more evidence rather than believing one source (like wikipedia!).

All these capabilities and even lessons all written up for a variety of levels can be found on the science online TKI site: http://scienceonline.tki.org.nz/Science-capabilities-for-citizenship/Introducing-five-science-capabilities.