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Setting the Stage for Student Sense-making in Science: Recurring Themes and Concepts

11 Min Read
Three educators talking hero WF1807234

How many times as a classroom teacher have you asked your students, “What do you observe?” When I was teaching middle school science, I remember on more than one occasion asking that same question. Often the lesson hinged upon the students noticing and wondering about an aspect of a video, demo, or some other stimulus to engage the students in the lesson. The students’ responses were varied and energetic…but none of them observed what I wanted them to observe. I often had to resort to simply pointing out the phenomenon, and as a result, I took away the students’ opportunity for discovery. It left me scratching my head. Why aren’t the students observing what was so obvious to me?

The answer to my question can be found in the K–8 Texas Essential Knowledge and Skills for Science (TEKS for Science), namely, the Recurring Themes and Concepts, or RTCs. The RTCs consist of recurring themes and make connections between overarching concepts. They include themes such as systems, models, patterns, structure and function, change and constancy, cause and effect, and energy and matter. Do these themes sound familiar? They should. In the 1993 publication Benchmarks for Science Literacy, part of AAAS’ Project 2061, these were referred to as Big Ideas or Themes. In the National Science Education Standards, they were called Unifying Themes and Concepts. So why were these themes, despite being around for so long, rarely used in the classroom? The answer is simple: we did not know their purpose and how to use them to help students make sense of the phenomena and problems they encounter in the classroom and in their lives.

Since the 2012 release of the A Framework for K–12 Science Education: Practices, Crosscutting Concepts, and Core Ideas, there has been a rejuvenation of how science is being taught and how students learn. The newly adopted K–8 TEKS for Science embraced this seminal document and incorporated the RTCs as one of the strands along with scientific and engineering practices, or SEPs, within the knowledge and skills that students should be able to gain proficiency over their K–12 experience in science education. As a result, the new K–8 TEKs for Science has made the RTCs more explicit in their description so that they would have more utility for educators and students.

What Are the Recurring Themes and Concepts (RTCs)?

There are seven Recurring Themes and Concepts, or RTCs, used as a framework to make connections across disciplines. Each RTC highlights a unique perspective where the student is led to ask productive questions to understand and explain the problem or phenomenon being investigated.

Recurring themes and concepts grades k thru 8 WF1807234

The RTCs help to guide and expand student thinking and serve as an aid in sense-making and problem solving. All too often we, as teachers, expect students to discover these lenses on their own, without ever discussing their use. Using the RTCs provides a pathway for investigation and helps students focus on aspects of a phenomenon or problem on which they can then employ scientific and engineering practices as tools for investigation.

The RTCs are essential elements to enrich the SEPs and concepts.

Purpose of the RTCs

The RTCs are conceptual tools for which students can use when examining unfamiliar situations to find an approach that helps with sense-making. It might be helpful to think of each RTC as a lens through which the student views novel problems or phenomena. The RTCs allow students to focus their thinking on a particular aspect of what they are observing. According to the 2008 book Ready, Set, SCIENCE! Putting Research to Work in K–8 Science Classrooms, when students are engaged in figuring out explanations of phenomenon using the SEPs and RTCs, they make their thinking visible.

Let’s look at an example.

Consider a middle school student observing water forming on the outside of a glass containing ice water on a humid day. Curiosity and wonder are natural stimulants that drive student motivation. Presented with a phenomenon, the student begins to gather information to satisfy their natural curiosity. Their first questions would likely be about the phenomenon.

  • Where does the water come from?
  • What makes the water form?
  • Why doesn’t water form on the outside of a hot coffee mug?

From these questions students can begin the sense-making process and gather further information. The students can incorporate the SEPs. For instance, they could develop models to show their initial ideas of what is causing the water to form on the glass. Using their models, they can plan and conduct investigations to test their models, analyze the results, and construct explanations of their investigation. Throughout this process of inquiry, the students are engaged in the same investigative process that scientists and engineers employ. Students also can revise their thinking based upon investigation experience and discourse with their classmates. In sum, they are actively figuring out the phenomenon rather than passively learning about it.

In theory this makes sense, but as classroom teachers know only too well, theory only works in publications. Let us reconsider our condensation example.

How can the teacher focus the student on the aspect of the phenomenon that is the focus of the lesson? The answer can be found in the way the teacher designs questions and prompts to the student.

  • If the teacher prompts students by asking, “what are some possible causes for water to collect on the outside of a glass of ice water?” the students’ thinking will focus on the RTC of cause and effect.
  • If the teacher prompts students by asking, “in what way did energy flow during the process of water collecting on the side of the glass?” the student will look at the phenomenon through the lens of the RTC of energy.

Notice how the specific RTC is embedded in the question or prompt. The RTCs help students to make connections across all science disciplines.

When designing lessons, teachers can decide what phenomenon is to be used for the lesson and what aspect of the phenomenon they want the students to focus on. Once decided, an important part of the planning process is for the teacher to craft specific prompts embedding RTCs within the prompt or question to be used during the lesson. Using these RTCs effectively supports student sense-making. Additionally, and thinking back to my reference to my frustration when I asked the open-ended “what do you observe?” question, by having students concentrate on specific aspects of the phenomenon, it helps to eliminate the “noise” and focus students on the phenomenon.

Time to reflect on the use of the RTCs is essential for students to construct explanations.

RTCs as a Progression

Within the entirety of the K–8 TEKS for Science, the RTCs are prevalent in every grade. They are intended to be a progression where the language and use of the RTCs increase with the grade level (see the table below). Students build upon their understanding and utility of the RTCs through their K–8 experience. This does not happen passively. Teachers must purposefully use the RTCs in their questions and prompts with consistency and establish expectations for the students to use the RTCs in their explanations. When teachers use RTCs as a consistent part of their discourse with students, the RTCs become part of the everyday language between teachers and students.

Grades K–2

Grades 3–5

Grades 6–8

Identify and use patterns to describe phenomena or design solutions.

Identify and use patterns to explain scientific phenomena or to design solutions.

Identify and apply patterns to understand and connect scientific phenomena or to design solutions.

Notice how the language changes in terms of the expectations of what the student will do when using the same RTC through grades K–8. This type of progression in language and expectation is consistent in all seven of the RTCs in the K-8 grade bands.

HMH Into Science Texas incorporates the RTCs within the lessons and ancillary materials to support implementation of the 2021 K–8 TEKS for Science. Inclusion of the RTCs in the series is designed to help students structure the way they are thinking when exposed to phenomena or design-based problems. The series also provides teachers with prompts and questions based upon the RTCs to pose to students in every phase of the lessons.

In this example, using a core idea expectation for kindergarten, students observe and identify the dependence of plants on air, sunlight, water, nutrients in the soil, and space to grow (TEKS for Science K.12.A). Using the phenomenon that plants have specific needs to grow here are some sample prompts that the teacher might use to initiate a discussion with students. Note that the RTC being used in these prompts is written in bold.

  • TEACHER: Think about the plant on the shelf in the classroom and a plant that you might have at your own home. What patterns do both plants have in common to grow
  • STUDENTS would think of patterns of things that plants and animals have in common. Sample responses: “the plant needs sunlight,” “the plant needs water,” “the plant needs soil.”

The teacher may go on to prompt:

  • TEACHER: What are some other things that would cause plants not to grow?
  • STUDENTS would shift their focus to what might cause the plant not to grow. Sample responses: “We had a plant at home, but we did not give it enough sunlight, so it died. Plants need a lot of sunlight.” “Plants don’t move around…they just sit there. But trees grow big and tall even though they don’t move. They must get their food from the roots.”

The teacher can guide students along the lesson phases with this questioning technique that uses the RTCs. Using the responses from the students during the engage phase the teacher can move into the explore phase using similar questioning techniques.

When asking for evidence behind their responses, often students include the RTC after having been prompted.

Teks k point 12 a ed screenshot WF1807234

A point-of-use prompt during the engage phase of HMH Into Science Texas helps students include an RTC in their response.

Having this ongoing dialogue with students needs to be present every day and requires the teacher to create carefully developed questions and prompts using the RTCs. RTCs are not used on a certain day of the week. Don’t treat them like tacos and only use them on “RTC Tuesdays!” On the contrary, if all Texas teachers, from K through 8, use RTCs in their questions and prompts, the sophistication of the student responses and sense-making will increase as students build on their understanding of the RTCs as a common language and apply them to new situations.


Recurring Themes and Concepts, or RTCs…

  • Provide a common language between the teacher and the student.
  • Are not passive questions at the end of instruction. They should be used throughout the entirety of instruction.
  • Are important tools for students to make sense of phenomena and problems.
  • Should become a common language between the teacher and the student. This language progresses throughout the student’s K–8 experience as understanding grows and is applied to different contexts.
  • Can be called upon as a common sense-making tool when confronted with novel or unfamiliar problems or phenomenon.
  • Are a lens to frame an aspect of a phenomenon or problem in a specific way. When using RTCs teachers should look at aspects that are relevant to the investigation that is being framed.

When using RTCs, teachers should…

  • Craft questions and prompts designed to focus students on specific aspects of the phenomenon or design-problem being addressed.
  • Provide students experiences where the RTCs are useful.
  • Ask students to use specific RTCs in their responses or written work as they cite evidence for their explanations. Have them reflect on how the RTC helped them understand more about what they are investigating.
  • Recognize that RTCs are only effective when they become familiar to the student.
  • Avoid the misconception that RTCs can only be addressed through a worksheet or as a response on a quiz or test, i.e., something that is tangible and easily measurable.
  • Understand that after using RTCs in their questions and prompts over time, they will notice students using the language of RTCs in their explanations to support their sense-making.
  • Gain a formative assessment perspective of student learning by providing evidence of the student’s progression through the sense-making process and through learning via discourse.

How I wish I had a working understanding of RTCs when I was teaching! However, my experience in the classroom has fueled my passion for these important, sense-making tools. As science educators our goal is not to simply “cover” the material but to support students’ development of skills and knowledge that they will carry forward throughout their lives. The RTCs are the lenses that will allow students to make sense across all domains of science and engineering. HMH Into Science Texas embraces the importance of the RTCs and provides teachers with the teaching approaches necessary to make a difference with every student.


HMH Into Science Texas and HMH ¡Arriba las Ciencias! earned 100% compliance on both the TEA and TRR reviews. Learn more about our K–8 science curriculum developed for Texas classrooms or contact your personal HMH rep today.

Be sure to join Peter McLaren’s workshops on the RTCs at CAST23, one of the nation’s premier science education conferences, in Houston, Texas on November 9–11, 2023.

HMH earned 100% compliance on the TEA and TRR Reviews!

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