First-Graders Modeling Day and Night: Making Sense of a Phenomenon

As a first-grade teacher in Detroit with predominantly Latinx students and English language learners, I worked for several weeks at the end of last school year with a doctoral candidate in science education and former elementary teacher, Christa Haverly, and by extension, an associate professor in science education and expert in scientific modeling, Christina Schwarz (see our bios below). We co-planned a unit around the Space Systems standards for first grade: 1-ESS1-1 and 1-ESS1-2 (see the table at the end).

We started the unit with this phenomenon and driving question:

During the unit, students engaged in many science practices, but we are focusing this blog post on their scientific modeling. In the NGSS, the primary purpose of engaging students in modeling is for them to use models to determine relationships between objects so they can explain phenomena in the natural world. To this end, I had students construct, share, and revise their models of the observed phenomena related to our overarching driving question.

We also kept a class model that we continued to update and revise through the unit (pictured is an early version of the model). It seemed useful for my students to have a place to share their ideas and keep track of them during their discussions. In that way, their models were useful for helping them make sense of day and night, a better option than me giving them models of day and night so they could tell me the science facts. I also found that modeling was a useful formative assessment tool, giving me richer insight into student thinking than traditional written assessments.

After a couple of weeks, it became clear that my students were ready to consider an important question about how the day/night cycle happens. We started by reviewing timelines students constructed the week before that plotted daylight and darkness in 24-hour cycles. Students recalled patterns from their data, and we agreed that there is a cycle of light and dark, day and night.

Next, I split students into pairs to role-play Earth and Sun. I gave them a flashlight to represent the Sun, and a sticker to place on one of their foreheads to represent Detroit on Earth. Once in the gymnasium, students took turns being the Sun and the Earth, and explored what kind of movement might create a day/night cycle like we observed in our data. Students’ ideas included the Earth rotating (while the Sun stood still), the Sun moving around the Earth (while the Earth stood still), both co-occurring, and the flashlight turning on and off (both stood still while Sun turned off and on). Many students ultimately tried keeping the Sun still while the Earth spun in place, mimicking the movement of the globe in our classroom.

Back in class, we debriefed and had students share the different ways they made day and night “happen” in Detroit. Next, we watched a video of the Earth rotating, a phenomenon which can’t be observed from Earth. Students discussed their new ideas with their partners and shared them with the class. They observed the Earth slowly spinning, and they also noticed the area illuminated by the Sun was slowly shifting as the Earth spun. During the discussion, one of my students noticed the classroom globe was also partially lit by the sunlight coming through the windows. He walked over to it, and as he turned the globe, he and his classmates saw new parts of the globe becoming light and dark.

I concluded the activity by asking students to create models showing how day and night happen on Earth. What do you see in these two images? What do they tell you about student thinking?

I think the one on the top shows that the side of the Earth facing the Sun is lit, and the side of the Earth facing away from the Sun is in darkness. The one on the bottom shows that the movement of the Earth rotating in a circle has something to do with the day and night cycle. While several students shared these ideas, others were still including images from their bedrooms, more concretely connecting with our original phenomenon, while still others were showing the Sun moving around the Earth. I used about half of students’ models the following day in a gallery walk, representing a range of ideas, and afterward, students discussed what they observed in one another’s models. Throughout the unit, I continued providing students with new experiences, followed by class discussions about patterns based on new evidence, and students continued creating, sharing, and revising their models.

I loved using the models as a way for students to analyze their ideas about our phenomenon and communicate their ideas to one another and to me in ways that did not rely heavily on writing or vocabulary, and for me to learn about my students’ thinking. What are some ways that you use models in the science classroom? Or what are some of the challenges you’ve experienced? Please comment so we can learn with and from one another!


Kim Sedlmeyer graduated from Michigan State University (MSU) in 2011 with a degree in elementary education. Since 2012, she has taught at Escuela Avancemos! Academy, a first-year charter school in Detroit. The Academy is a Success for All school, and Sedlmeyer serves as Reading Roots Chair. Her other passion is dance, and she shares this passion with students every year by directing the school’s Nutcracker program and performances.

Christa Haverly is a doctoral candidate at MSU studying science teacher education, with an emphasis on urban elementary education. Her research centers on teachers’ pedagogical practices that are responsive to students’ science ideas and are socially just. Before beginning graduate school, she taught elementary school for a decade, working in three different urban elementary schools in Maryland and Illinois.


Christina Schwarz is an associate professor of teacher education at MSU. She is a co-editor and author of the NSTA Press book Helping Students Make Sense of the World Using Next Generation Science and Engineering Practices. She has served as subject-area leader in elementary science at MSU for more than a decade and enjoys working in classrooms with teachers and students. She hopes readers will be able to explore and enjoy modeling as much as she does.


This article was featured in the August issue of Next Gen Navigator, a monthly e-newsletter from NSTA delivering information, insights, resources, and professional learning opportunities for science educators by science educators on the Next Generation Science Standards and three-dimensional instruction.  Click here to sign up to receive the Navigator every month.

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What Is Your Model For?

Recently, my colleagues and I had an exchange with some teachers in one of our professional development programs. One teacher said, “I think I do a lot of modeling in my class. I have my kids draw pictures of the science ideas they are learning all the time.”

This description of modeling is common. When we ask our colleagues, either informally or in professional development settings, about their current teaching and the practice of developing and using models, they often respond that they consider models as things like 3-D replicas or drawings. They say, “I have my kids make models of cells, the solar system, the water cycle, atoms, and so on.”

This type of “modeling” activity might sound promising, but it often doesn’t fully realize the potential of the modeling practice. It’s not surprising, though, that this conception of modeling is so pervasive because much of the available information on modeling focuses on drawing as a way to bring kids into this practice. In our experience with modeling, we’ve found that a depiction—usually a drawing—focuses our attention on a surface feature of the practice and not on the deeper knowledge-building potential. 

For example, teachers might typically ask students to draw a model of the pond ecosystem, or draw a model of the forces acting on a ball as it rolls down a ramp. But without a clear purpose, students might be confused about how they should interpret these tasks and can’t properly judge their ideas, leaving them to appeal to the teacher or textbook as authority. “Is this right?” is what most students will inevitably ask.

Continue reading …

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Modeling in Science Instruction

With the shift toward three-dimensional teaching and learning that the Next Generation Science Standards requires, the Crosscutting Concept of Modeling has become a major focus of my instruction.  I use a process that involves revisiting the same model at least three times in a unit to support students’ growth in this area.

Each unit starts with a puzzling phenomenon that can be fully explained by the concepts covered in the unit. Students observe the phenomenon in a video clip or demonstration, then draw a concrete model of what they observed. For more complex, multi-step phenomena, I give them basic drawings of the areas to focus on; they can add details to these drawings.

Once they have a complete drawing, they label and describe what they think is happening and why. These initial models are often basic and full of misconceptions. I find this very informative because I see exactly what they know and understand at the start of the unit.

Students have an opportunity to give and receive feedback using sentence stems on their initial models.  Each student is given stickynotes and asked to provide at least one positive and one constructive comment for three different students. Examples of positive sentence stems are “I like how you…” and “When you did _____, I could really understand it.” Some constructive feedback stems are “The part about ____ is a bit unclear”  and “You could…” or “Have you thought about including …?”

Continue reading …

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Ed News: New Girl Scout STEM Badges & Back-to-School Spending Hits $82 Billion

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This week in education news, the Girl Scouts have added 30 new badges in STEM to encourage more female involvement; back-to-school spending will hit $82.8 billion for K-12 and college combined, and more teachers are digging into their wallets; and meet astrophysicist – and NSTA President-elect—Dennis Schatz.

Girl Scouts Launch New STEM Badges

The Girl Scouts have added 30 new badges in science, technology and engineering to encourage more female involvement in STEM. Girl Scouts CEO Sylvia Acevedo joins the ‘Power Lunch’ team to discuss how the non-traditional activities will help girls adapt to a changing world. Read the article featured on

Teachers Must Budget For Hundreds Of Dollars In School Supplies

Kids love it, parents may dread it, but one thing’s certain: The annual school shopping ritual is a smack to the wallet every year. This year, back-to-school spending will hit $82.8 billion for K-12 and college combined, according to the National Retail Federation’s annual survey. That’s almost as high as last year’s $83.6 billion. Read the article featured on

Working Geek: A Star In Science Ed, Astrophysicist Dennis Schatz Wants To Expand Minds

Schatz is a solar astrophysicist by training, has written 25 science books for kids and last year Asteroid 25232 was renamed Asteroid Schatz by the International Astronomical Union’s Minor Planet Center in honor of his dedication to science education. He’s worked for the Science Center for four decades. Read the article featured on

1st Of Christa McAuliffe’s Lost Lessons Released From Space

The first of Christa McAuliffe’s lost lessons finally was released from space Tuesday, 32 years after she died aboard Challenger. Read the article featured in Education Week.

8 Apps You Should Check Out Before School Starts

Check out this list of apps, ranging from kindergarten through high school and touching on topics such as STEM, history, and vocabulary. Read the article featured in eSchool News.

Stay tuned for next week’s top education news stories.

The Communication, Legislative & Public Affairs (CLPA) team strives to keep NSTA members, teachers, science education leaders, and the general public informed about NSTA programs, products, and services and key science education issues and legislation. In the association’s role as the national voice for science education, its CLPA team actively promotes NSTA’s positions on science education issues and communicates key NSTA messages to essential audiences.

The mission of NSTA is to promote excellence and innovation in science teaching and learning for all.

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Freeze! We’re doing science!

I have accumulated a large number of the freezer gel packs from a meal service. I’d like to find a way to use them in a classroom activity.
—P., Georgia

The best thing about these freezer packs is that they provide a constant that will help your class design and conduct a lot of experiments. Reusing these in your classroom is also a great environmental message.

A few ideas for experiments :

  • Engineer the best picnic cooler. (Save styrofoam boxes and pellets from shipments you have received).
  • Determine the optimum place to put a freezer pack in a standard cooler.
  • What conditions speed up/slow down warming or cooling? Correlate the data with ambient temperature.
  • Investigate the heat conductivity of different solids and liquids. Put the packs in ziplock bags and immerse them in oily/messy liquids.
  • Surface area experiments: curl them up, lay them flat, stack them vertically/horizontally, spread them out. Relate this information to physical science, chemistry and even biology.
  • The contents of freezer packs are non-toxic. Open them up and do carbohydrate, lipid, protein, and other chemical tests on the contents.
  • Place them on different parts of the hands and arms to create a cold sensitivity map.

As useful tools:

  • Keep them in the freezer to use instead of ice cubes for chemistry or biology activities.
  • Putting live insects in a freezer for a few minutes will slow them down. Place the gel packs under the insects to keep them cool while observing them with microscopes or magnifying glasses.

Hope this helps!


Photo credit: By Dhenning2005, aka Dave Henning [Public domain], from Wikimedia Commons

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Moving water involves using the practices of science and engineering 

Child pouring water from a container onto a curved trough-like piece of bark set at an incline.Sometimes the discovery of materials on a play area inspires children’s exploration and use of the NGSS science and engineering practices

In this example a long length of bark from a tree branch became a trough for investigating water flow.

At first the 5 year old simply put the curved length of bark at an incline to make a path for water which was being used elsewhere in the outdoor play area. Her choice was likely informed by her prior experiences with balls and ramps, and in water play. In her actions she is planning and carrying out an investigation, asking what will happen to the water as it moved from a container onto the bark trough and trying to solve the problem of designing a system to carry water. A teacher supported her by standing nearby and watching intently, showing interest, and asking a few open-ended questions. “Where is the water going?” “What might happen if you drop the water from a higher up or a lower down?”

The child poured water into the trough at the top, watching it flow down and soak into the sand. Then she added another container at the bottom to try to catch the water. Additional children joined in. Repeatedly pouring water into the top of the length of bark made the children certain that very little water was being captured by the container at the bottom.

The first child redesigned the system, moving the length of bark to balance on top of two containers at the ends of the length (K-PS2-2 Motion and Stability: Forces and Interactions). She observed while pouring the water into the middle of the horizontal trough. Where do you think the water flowed in this new system design? Child pouring water into horizontal trough from higher up.

There was time for one more redesign before going indoors for lunch. She added a third container on top of the trough in the center and poured water on top of the upside-down container. Where do you think the water flowed in this new system design?

The child put a third container on top of the trough and pours the water on top of this third container.

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Ecosystems: Recycle and Cycle

Do you have any advice for creating bottle ecosystems with my seventh grade class? I would like them to do two-tier systems with terrestrial and aquatic organisms.

—S., Missouri

Students can learn a lot when they create these micro-habitats in plastic bottles with plants and invertebrates. The bottles can be stacked to form interdependent aquatic and terrestrial ecosystems. I’ve collected some resources in the NSTA Learning Center ( with more information.

Start the project by going over the different types of ecosystems and organisms. To get the organisms, you can sample a pond, flip over rocks and even visit a pet store before “build day.” I always kept a stock of these year-round in terraria and aquaria in my classroom. After spending a class researching the organisms available, students create a “shopping list” of the materials they need to add in their ecosystem. Have students bring in the two-liter bottles or ask colleagues for donations. Spend a class building the ecosystems and starting seeds of fast-sprouting plants like oats, radishes, greens, and alfalfa. Some students may want to use samples from an aquarium in their aquatic ecosystems. Have them explain why in their journal. A fleece wick between the lower, aquatic ecosystem to the upper, terrestrial ecosystem will facilitate water movement. In a few days the plants will sprout and students can add the invertebrates

Have the students write journal entries at least twice a week and stress accurate observations. If available, use oxygen and carbon-dioxide sensors as part of their data collection. Bio-geochemical cycles, pyramids and food chains/webs that depict their bottles can be incorporated into their journals.

I love bottle ecosystems and so did my students!

Hope this helps!


Photo by author

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Ed News: K12 Educator Externships Provide Practical STEM Experiences

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This week in education news, maker spaces help teach students to redesign their worlds; educator externships provide hands-on authenticity that better informs instruction and boosts teacher confidence; teachers wish they had more opportunities to further their careers while remaining in the classroom; across the country, most teachers don’t receive enough money to equip their classrooms and keep them running; President taps Kelvin Droegemeier as next White House science adviser; and Florida’s talent gap persists in the STEM occupations, despite the state’s booming economy.

‘I Can Do That!’: How Maker Spaces Teach Students to Redesign Their Worlds

As schools nationwide are expanding the use of maker spaces, researcher Edward Clapp spoke with Education Week about how teachers can get it right. Clapp is senior research manager on the Agency by Design initiative at Harvard University, which examines the promises of maker-centered learning. Read the article featured in Education Week.

K12 Educator Externships Provide Practical STEM Experiences

An externship program run by the Oklahoma State Department of Education expanded this summer, allowing K12 teachers to gain professional STEM experiences they can bring back to the classroom. During the pilot last year, teachers tested soil samples and worked in a concrete-making lab, among other activities, during a paid two-week externship at an Oklahoma City engineering firm. Read the article featured in District Administration.

Continue reading …

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NSTA Legislative Update: CTE Bill Signed & Making STEM a Priority in FY2020

President Trump Signs Career and Technical Education Bill

Congress finally passed, and President Trump signed into law, a reauthorization of the Carl D. Perkins Career and Technical Education Act on Tuesday, July 31.

The bipartisan bill, which has not been reauthorized since 2006, will provide $1 billion to states for secondary and post-secondary skill training.  It has the support of governors, the U.S. Chamber of Commerce and most education groups and was heavily championed by the Administration, notably the president’s senior adviser Ivanka Trump, who has made workforce issues a priority.  

During the signing of the Strengthening Career and Technical Education for the 21st Century Act President Trump said, “we will continue to prepare students for today’s constantly shifting job market, and we will help employers find the workers they need to compete.”

The new law will apply to the 2019-2020 academic year. It allows states to set their own career and technical education goals and it eliminates an existing negotiation process between states and the Education secretary, who still approves the state plans.

Continue reading …

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Fire Air Dephlogisticated and the Vernier Go Direct Wireless Oxygen Sensor

Oxygen is one of those very cool elements that can both save a life and kill whether in absence or abundance. Oxygen is necessary for life as we know it, but yet it oxidizes one of the most common elements in the universe. Oxygen, to most students, is both a red ball on a model and a common test question answer. But to fully appreciate oxygen, students need to measure it. And as an odorless, tasteless, colorless gas, oxygen is filled with surprises, and also science essentials.

The history of the discovery of oxygen has plenty of twists and turns stretching from the second century BCE to the present. The path to discovery and understanding of oxygen is truly a who’s-who of science and philosophy. Whether Philo of Byzantium or Leonardo da Vinci or Robert Boyle or Antoine Lavoisier, or even Charles Darwin, the road to oxygen is paved with greatness. And don’t forget that Robert Goddard, the father of modern rocketry was the first to use liquid rocket fuels and one of those was liquid oxygen.

The Extinction of Words

A notable causality of the progression towards the understanding of oxygen was the word dephlogisticated. Back about the time America was just starting its grand experiment, around 1776, the word dephlogisticated was used to describe the portion of air now known as oxygen. Unfortunately for the word dephlogisticated, however, as the pace of science increased so the need for the word dephlogisticated decreased. Dephlogisticated, by the way, means dephlogisticated or without phlogiston. Ok, so much help with that. So a better explanation might be that phlogiston is a chemical involved with combustion. So dephlogisticated is the lack that chemical.

Regardless, the use of the word dropped of off a cliff after 1800. Presumably the speed of “viral” back in the 19th century would be on the speed of decades. So Dephlogisticated died a quick death over a 25 year period. By 1825, the word was at risk. By 1875, the word was on the endangered species list. And at the beginning fo the 21st century, the word was only found in museums and zoos and historical footnotes like this blog. Continue reading …

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