#20 – How we use Chocolate Milk and TV Snacking as CER practice examples (note: real science examples!)

Do you know about the Four Stages of Competence? One of its claims is that getting better at a skill (to go from “conscious” to “unconscious competence”) requires practice. Of course, this is nothing new. To get better at sports, reading, writing, or arithmetic requires practice to hone the craft. Using CER – Claim, Evidence, and Reasoning – to analyze science research is no different. How do students get better at writing claims and supporting those claims with clear evidence and reasoning? Students need practice. In Blog #9 (Does Aspartame help with weight loss? 3 CER practice activities from real science data), I provide some sample research from real science research for CER practice. Unfortunately, many educators find the articles to be too complex for their students. So, this time, I offer simpler CER practice examples.


This time, we selected our graphs and data from research articles based on a couple of big questions. (1) Can students read and understand the graphs without extra information or instructions? And, (2) will students find this topic fun or interesting? From those 2 questions, we sifted through countless research articles from the Public Library of Science website and found two articles that fit the criteria. We summarize the research question, experimental methods, and data below. You can also download our handouts (with all the CER practice examples below nicely formatted as a pdf) along with our sample key at the end of the post.



Present the following CER practice examples (the research studies and accompanying data) to students and have them come up with a CER (Claim Evidence Reasoning) paragraph on their own or in groups. I usually ask this in 3 steps:

  1. [Claim] What is a conclusion you can make from the data?
  2. [Evidence] How does the data support your conclusion?
  3. [Reasoning] Drawing from scientific theories or other studies, why do you think this happens?


CER Practice Example 1: Banning Chocolate Milk


Research Question:

Chocolate milk can have up to two times more sugar than white milk and, as a result, removing chocolate milk from school cafeterias has been debated as a way to reduce childhood obesity. Researchers studied the effect of removing chocolate milk from cafeterias on milk selection and consumption.


Experimental Design:

Researchers recorded how much milk was sold at 11 elementary schools in September and October of 2011, when chocolate milk was available for purchase in the cafeteria (chocolate, 1%, and skim were the only milks available for sale). In September and October of 2012, chocolate milk was no longer available for purchase in the cafeteria, and researchers again recorded how much milk was sold for the same 11 schools.





Hanks AS, Just DR, Wansink B (2014) Chocolate Milk Consequences: A Pilot Study Evaluating the Consequences of Banning Chocolate Milk in School Cafeterias. PLoS ONE9(4): e91022. https://doi.org/10.1371/journal.pone.0091022



CER Practice Example 2: Snacking and Television Shows

Research Question:

Obesity rates have more than doubled since 1980. There are variety of lifestyle factors that have contributed to this increase. For example, in some studies, researchers have linked watching TV to increases in food intake and, as a result, weight gain.
In a study, researchers in Sweden studied the impact of television content has on food consumption.


Experimental Design:

Researchers had 18 female participants do three activities: read for 30 minutes of non-engaging text (ie. a text on insects living in Sweden); watch 30 minutes of television with boring, unengaging content (ie. an art lecture on public Swedish television), and watch 30 minutes of television with exciting, engaging content (ie. a popular Swedish comedy sitcom). Researchers also provided participants with food (grapes and chocolate). As participants were doing each activity, researchers measured how much food was consumed by each participant.





Chapman CD, Nilsson VC, Thune HÅ, Cedernaes J, Le Grevès M, Hogenkamp PS, et al. (2014) Watching TV and Food Intake: The Role of Content. PLoS ONE9(7): e100602. https://doi.org/10.1371/journal.pone.0100602



Wrap Up

Using CER is like any skill. It requires practice to get better at it. Unfortunately, CER practice comes from analyzing data sets, other research studies and science phenomena – all of which may not be that easy to find. But, when it’s done right (engaging and relevant to students), it’s pretty sweet. Click the link below to join our email list and download our handout (which include the CER practice examples above and our sample key).


For More Fun CER Practice Examples Handout, Click here!


Until next time, keep it REAL.

Posted on November 7, 2017 in Strategies

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