Scientific Modeling

I didn't really understand what a scientific model was, or its importance, until I started diving into NGSS a few years ago. Each year since, I've continued to try to refine and improve how I teach and assess this practice with my students. Currently, I assess their ability to create a scientific model and their ability to evaluate a preexisting scientific model.

This week, I started with my Honors Biology students on the "designing a scientific model" journey. We began by discussing a model they were already familiar with - the Rutherford atomic model - and sharing thoughts about what that model explains to us about atoms. Luckily, one of the students piped up and reminded the class the Rutherford model is no longer considered "correct," which led us right into a discussion about how as scientific explanations change, models will also change.

Last week, the students collected data on heart rate associated with various cardiovascular activities. Although they had already completed a scientific argument based on the data, next I wanted them to design a model to show their explanation of the data. We worked together as a class to create a model for the results of one of the independent variables, and then they practiced making a model for a different independent variable on their own. Finally they self-assessed their model based on this rubric:

This rubric is a screenshot from Schoology. It's definitely a work in-progress. If you have any feedback, I'd love to hear it!

Now it was time for them to try to create a model with new data on their own. In order to continue down the path of our guiding essential question, the students completed an investigation into muscle fatigue, which involved squeezing a tennis ball under different temperature conditions. Once they had the data, and watched a short video introduction to anaerobic respiration, it was time to see if they could make a model to explain the differences between two different temperatures. I have not yet looked over their work, but I'm hoping to see some growth. As a warm-up at the beginning of the week, I had the students create a model of how a rainbow is formed, and then they did it again at the end of the week. I saw improvements in this task, so I'm optimistic for their muscle fatigue models.

Honors Biology students collecting data for the Muscle Fatigue investigation.

Anatomy & Physiology students creating 3-D tissue models for peer-to-peer instruction.

Reconnecting & Reflecting

Although last year was an amazing adventure as my first year teaching in Seoul, it was a dismal year for my blog as I only posted a handful of times. One of my goals for this year is to reconnect with my PLN, and being more active on this blog is a part of that. Beyond all the transitions involved with an international move last year, I think part of the reason I didn't blog as much was because I didn't have any big ideas I felt like sharing. But I've realized many of the blogs I like to read aren't necessarily about "big ideas" - they're just a peak into the day to day life of a classroom.

So, with all this in mind, my blogging plan for this year is to post one day a week, focusing on reflections from the past week's classes. I'm teaching Honors Biology (9th grade), Honors Anatomy & Physiology (11th & 12th grade), and AP Biology (11th and 12th grade) this year, and I may or may not write about every class each week.

Without further ado...Here's what we did this past week!

Honors Biology
I introduced the idea of scientific argumentation to my 9th graders during the first week of school. The CER framework was brand-new to them, so I had them practice it in pieces. They put all of those pieces together in a full written argument last week, and the results were daunting. It was clear the students were still struggling with data analysis and applying science ideas to explain data. I needed to hit the brakes and revisit CER.

Since we're in the middle of exploring a phenomenon associated with healthy diet and weight (involving NGSS standards on biomolecules and cellular respiration), at the end of last week the class worked together to design an experiment that required them to collect heart rate data for various cardiovascular activities. I then worked with them step by step to analyze the data, modeling how to sort on a spreadsheet, how to account for outliers, when to average data, how to judge whether data is reliable, and how to discuss trends and patterns in data. Students worked in partners and used their whiteboards to write a Claim and Evidence for the cardio data. Using whiteboards was great for this because as I circled the groups and gave them feedback they needed to make lots of changes, which is easy to do on a whiteboard. Also whiteboards are easier for me to read than a lap top screen or notebook page when I'm on the move around a classroom. Many groups filled two whiteboards as I prompted them to fully and specifically support their claims.

I used a similar strategy for the Reasoning section - student pairs working on whiteboards. During this time, most of my prompting was asking, "why?"

Student: Jogging increased heart rate more than playing basketball.
Me: Why?
Student: Because you're moving more when you're jogging.
Me: Why does moving more increase your heart rate more?
Student: Because you need more oxygen.
Me: Why?
Student: Because you need more energy.
Me: Why do you need energy to jog?
Student: To move the muscles.
Me: How are energy and oxygen related?
Student: Oxygen is needed to make ATP in cellular respiration.
Me: And what does heart rate have to do with that?

I think you get the idea. Initially, this student's Reasoning would have simply begun and ended with, "You're moving more when you're jogging." I'm working to help them better understand how deeply they need to dig to truly justify their claims.

The culmination of all this practice was a chance to go back to their original argument that was initially so challenging for them and, redoing and revising it with their improved understanding of the process. I have yet to look over their work, but if their questions during the process are an indication of their new thinking, I believe some positive progress has been made.

Pre-assessment in Anatomy: Outline a body and draw a list of structures where you think they are located. Structures from different systems were drawn in different colors.

AP Biology students started out their year by designing an investigation of ant behavior.

Anatomy students participating in a model for homeostasis: "Homer-ostasis" requires them to keep the yellow "Homer Simpson" cup full, yellow, and at the correct temperature, despite a hole in the bottom.

First attempt at a scientific argument using the CER framework with AP Biology students. This is new to most of them as well, so we've got some work to do as a class.

Yes, Science Is Still Happening!

A collection of photos to highlight some of the things happening in the APIS Biology classroom recently. I know the blurred faces are creepy, but it's a school policy when sharing pictures of students...

LEGO League in Seoul! We weren't quick enough to get registered for the official competition this year, but the kids made up their own obstacle course. They're currently programming the robot just as they would if they were competing and will share their work at the school's International Fair at the end of March. The student in the back is my 12 year-old son, Egen, so no face-blurring required, which is awesome because I love the fact that I caught him mid-laugh.

Cell membrane bubble model. I really love this activity, not only because the students enjoy it so much, but also because they truly understand membranes better afterwards. I had them write a model evaluation after the activity, and the amount of learning they exhibited was astounding.

Building water filters in Environmental Science. This was their first engineering challenge of the year. The activity I based it on had restraints in material usage and cost, and the student teams all took different approaches to those constraints.

Another favorite: The sinking leaf disk assay. The students all perform the protocol the same way once, and then choose their own variables. This year, I asked them to write a scientific argument for their results and create mini-posters. There was much deep thinking when they started working on the Reasoning section of their arguments, trying to understand and explain their results. They also did some pretty sophisticated statistical analysis with the data this year.