Recurring Themes and Concepts (RTC)

Below are the 7 Recurring Themes and Concepts (RTC) in the new Science TEKS with vertical alignment of Student Expectations K - 8:

Cause and Effect

Flows, Cycles, and Conservation


Scale, Proportion, and Quantity

Stability and Change

Structure and Function


Science is a subject that is based on recurring themes and making connections between concepts (big ideas). Scientists use these themes to understand the world around them. 

One of these themes is structure and function, which means that everything has a certain structure that allows it to perform a specific function. 

Another theme is systems, which refers to how different parts work together to create a whole. Scientists use models to represent these systems, which can be observed, measured, and tested. All systems have basic properties that can be described in space, time, energy, and matter. These properties help scientists understand how systems work and how they change over time. 

Change and constancy occur in systems as patterns and can be observed, measured, and modeled. These patterns help to make predictions that can be scientifically tested.

Models are important tools for scientists to use when trying to understand complex systems. However, models have limitations, and it's important for scientists to understand these limitations. 

When students study a system, they need to analyze the system in terms of its components and how these components relate to each other, to the whole, and to the external environment. This helps students understand how systems work and how they can be improved.

RTC Cards

RTC Cards.pdf

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