Science Topics

7.1 Chemical Reactions How can we make something new that wasn’t there before?

Students develop and use a model of atoms and molecules to represent different substances and how they are rearranged and mass is conserved in chemical reactions. Students investigate property changes in the stuff they have before and after a chemical reaction and after a phase change to argue for whether new substances are created in these processes

7.2 Energy in Chemical reactions How can we help people make a flameless heater?

Students develop a model of energy transfer in chemical reactions and design a device to transfer the thermal energy produced from a chemical reaction to other parts of a system.

7.3 Metabolic Reactions How do things work inside our bodies to make us feel the way we do?

Students build on their model of energy and chemical reactions to explain how humans and other animals get the energy they need to survive and the building blocks to grow from the food that they eat. Students explain how this matter and energy transfer occurs as cells can make new substances out of food molecules through chemical reactions.

7.4 Matter and Cycling Where does food come from and where does it go next?

Students build on their model of energy and matter in food to investigate how food molecules become a part of the food they eat (both natural and processed foods). Students investigate how plants make food molecules and the source of the matter and energy needed for this process to do this. Students develop a model to explain that the major atoms that make up food (carbon, hydrogen, and oxygen) are continually recycled between biotic and abiotic parts of our world.

7.5 Ecosystem Dynamics and Biodiversity How does a change in an ecosystem affect what lives there?

Students investigate how interactions among organisms and changes to the environment (e.g. resource availability) can affect population sizes. Students develop a model including different type of relationships (competitive, predatory, etc.), and biotic/abiotic interactions to explain stability and change in ecosystems.

7.6 Earth’s Resources and Human Impact How do changes in the Earth's system impact our communities and what can we do about it?

Students investigate the uneven distribution of water, mineral, and fossil fuel resources on the planet. Students investigate how increase in human populations and percapita resource consumption affects Earth’s natural systems (climate, biosphere) in potentially hazardous ways. Students investigate natural carbon sinks, carbon sources, and the movement of carbon from fossil fuels into the atmosphere. Students develop a model of changes in the Earth’s climate system, and design systems to mitigate human effects on natural systems.