The content strands taught in third-grade science are listed below, along with some topics covered under those strands.
Scientific and Engineering Practices:
Scientists
Experimentation
Modeling and Simulation
Analyzing Data
Force, Motion, and Energy:
Simple and Compound machines
Forces impact on an object
Matter:
The three phases of matter
How materials interact with water
Living Systems and Processes:
Animal adaptations
Fossils
Living and Non-living things
Ecosystems
Earth and Space Systems:
Soil
The Water Cycle
Earth Resources:
Human impact on the planet
Water as a resource
Naturally occurring impacts on the environment
Soil as a resource
Attached are the Virginia 3rd Grade Learning Standards and Curriculum Framework if you would like more information and details.