Decoding Ice Cores: Proxy and Direct Measurement

Notes from our reviewers

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• Teaching Tips
  Teachers working with a middle school audience might think about scaffolding some of the student material in lab #2 by providing sentence stems for the four-step proxy model development, or completing one of the data examples together as a class. Teachers could avoid purchasing materials by printing images of tree cores and ice cores for lab #1. Science teachers may collaborate with math teachers in Lab #2 as students apply slope and best fit lines to create models of data. Students should have a good understanding of slope-intercept equations prior to completing lab #2, which is a math concept developed in 8th grade Common Core Math Standards, so lab 2 might not be appropriate for 6/7th graders. These labs require both time and material prep. Once all of the materials are obtained, teachers should plan to spend 1-2 hours familiarizing themselves with the material and prepping lab stations. This resource provides extensive background materials for the instructor to understand core concepts. However, it is unclear if the instructor is meant to lecture to the students using this information. Likewise, the theory behind the laboratory and graphing exercises is clearly outlined but there are no explicit instructions on how to organize the activity in a classroom setting. Student worksheets and teacher resources are included in the same Google document. However, in lab #2, the answers are written into the student worksheet. Teachers could make a copy of the document to delete the answers on the student worksheet.
• About the Science
  This resource helps students understand the difference between direct measurements and proxy models in science. It uses data sourced from NOAA, as well as data collected from students themselves. These labs support students' understanding of how we are able to make inferences about past climate conditions using proxy data The activities challenge students to apply concepts of modeling, including line of best fit and slope, to predict dependent values from independent values by using tree-ring and ice cores as examples. Students also use a claim and evidence model to reach a conclusion that is supported by data from the activity. Activities also support soft scientific skills such as collaborating with peers and reaching a consensus. Passed initial science review - expert science review pending.
• About the Pedagogy
  This resource includes two student labs that build off of one another. The labs could be completed together (recommended) or on their own. Students are asked to work together to graph, analyze, and interpret data. Lab #1 also encourages students to engage in discourse to find consensus. Teachers are encouraged to hold a class discussion about the data collected in Lab #1. Consider using this activity to support a discussion of how models can be used to predict future values in climate science. This activity can also be used to support a discussion on the climate change denial rhetoric around proxy models. Teachers can highlight the peer review process in science and discuss how multiple lines of evidence are used to reach a conclusion.
• Technical Details/Ease of Use
  Both labs can be downloaded as google docs. Teachers can make a copy of the google doc to edit and adjust as they please, and print the pages needed to complete the labs. Be sure to click "open as google doc" after clicking "download lab" as the images block text in the first view. This activity requires teachers to purchase materials to use as model ice core and tree core samples, as well as a number of supplies that may or may not be readily available in a science classroom (digital scales, graduated cylinders).