EALR 1: Systems. Big Idea: Systems (SYS). Core Content: Role of Each Part in a System
In prior grades students learned to recognize part-whole relationships. In grades 2-3 students learn to think systematically about how the parts of objects, plants, and animals are connected and work together. They realize that the whole object, plant, or animal has properties that are different from the properties of its parts, and that if one or more parts are removed, the whole system may not continue functioning the same way. Students also note cases in which the same part may play a different role in a different system. Finally, they learn to define system as "a group of interacting parts that form a whole." Understanding that an object, plant, or animal is more than the sum of its parts is a deep insight that has value in investigating all natural and human-made systems.
In prior grades students learned that scientific investigations involve trying to answer questions by making observations or trying things out. In grades 2-3 students learn to conduct different kinds of investigations. Although students may not yet be able to plan investigations alone, they can carry out investigations in collaboration with other students and support from the teacher. Actions may include observing and describing objects, events, and organisms, classifying them and making and recording measurements. Students should also display their data using various tables and graphs, make inferences based on evidence, and discuss their results with other students.
In earlier grades, students learned to use simple tools and materials to solve problems in creative ways. In grades 2-3 students develop the ability to design a solution to a simple problem, using an elementary version of the technological design process. They also increase their abilities to use tools and materials to design and build something that solves a problem. Students can apply these abilities in their daily lives.
EALR 4: Physical Science. Big Idea: Force and Motion (PS1). Core Content: Force Makes Things Move
In prior grades students learned to use appropriate words to describe the position and motion of objects and the effects of forces on objects. In grades 2-3 students learn that forces work not only to push and pull objects, but also affect objects when they are dropped or thrown. Whenever the motion of an object changes, there is a force involved. Greater forces on a given object result in greater changes of motion. In addition to being able to describe how forces change the motion of objects, students are expected to measure the position of objects using measuring instruments such as rulers. Students can also measure time to the nearest minute. Emphasis should be on comparisons of forces and motions rather than on calculation so that students develop conceptual understanding of how forces make things move.
EALR 4: Physical Science. Big Idea: Matter: Properties and Change (PS2). Core Content: Properties of Materials
In prior grades students learned about liquids and solids. In grades 2-3 students learn to identify different physical properties of materials (matter) and to realize that an object may be made from several different types of materials. They also learn that properties of materials change when environmental conditions change. Water, for example, changes to a solid when the temperature drops below 0° Celsius. Although few students at this age will fully understand that water may change to an invisible gas (e.g., water vapor) when left in an open container overnight, they can start to become familiar with changes of state by observing ice cubes freeze and then melt, and seeing water turn to steam when heated. Looking closely at matter to describe its characteristics will eventually lead to understanding the basic nature of matter and its physical and chemical properties.
EALR 4: Physical Science. Big Idea: Energy: Transfer, Transformation, and Conservation (PS3). Core Content: Forms of Energy
Students learn to identify several different forms of energy. Children in this age range have an intuitive understanding of energy concepts. For example, energy is needed to get things done; humans get energy from food. It is possible to build on these ideas by having the students explore different energy phenomena.
EALR 4: Earth and Space Science. Big Idea: Earth in Space (ES1). Core Content: The Sun's Daily Motion
In prior grades students learned that some of the objects they see in the sky change from minute to minute, while other things can be seen to follow patterns of movement if observed carefully over time. In grades 2-3 students learn that carefully observing and recording shadows provides an excellent way to trace the daily apparent movement of the Sun through the sky, which extends their observational skills. In later years, students will use this knowledge to realize that the Sun's apparent movement reflects Earth's daily spin on its axis.
EALR 4: Earth and Space Science. Big Idea: Earth Systems Structures and Processes (ES2). Core Content: Water and Weather
In prior years, students learned about Earth materials through their own observations. In grades 2-3 students learn that water exists in various locations and plays an essential role in Earth systems, including shaping land forms and weather. Weather changes from day to day, and weather conditions can be described by measurable quantities, such as temperature and rainfall. Environments can be affected by natural causes. Some of these changes are gradual and some are rapid. Water is essential for life, but it can also be destructive when too much is deposited too rapidly.
EALR 4: Earth and Space Science. Big Idea: Earth History (ES3). Core Content: None
No standards for 2-3 Earth History because content on fossils would duplicate content in 2-3 LS3 Biological Evolution.
EALR 4: Life Science. Big Idea: Structures and Functions of Living Organisms (LS1). Core Content: Life Cycles
In prior grades students learned that living things have basic needs and they meet those needs in various ways. In grades 2-3 students learn that all plants and animals have life cycles. They also compare the life cycles of a few common animals to see how they are similar and how they are different, and learn about the life cycles of plants. Focus should be on observable characteristics of how plants and animals change over time. An important aspect of life cycles is that plants and animals resemble their parents. This is a first step in understanding how the structures of plants and animals develop and function.
EALR 4: Life Science. Big Idea: Ecosystems (LS2). Core Content: Changes in Ecosystems
In prior grades students learned that all plants and animals live in and depend on habitats. In grades 2-3 students learn that ecosystems include plant and animal populations as well as nonliving resources. Plants and animals depend both on each other and on the nonliving resources in their ecosystem to survive. Ecosystems can change through both natural causes and human activities. These changes might be good or bad for the plants and animals that live in the ecosystem, or have no effect. Humans can protect the health of ecosystems in a number of ways.
EALR 4: Life Science. Big Idea: Biological Evolution (LS3). Core Content: Variation of Inherited Characteristics
In prior grades students learned that some objects are alive and others are not, and that many living things can be classified as either plants or animals. In grades 2-3 students learn about variations in inherited characteristics. That is, when plants and animals reproduce, the offspring closely resemble their parents. But the offspring are not exactly the same as their parents. Variations among animals and plants can help them survive changing conditions. Those plants and animals unable to survive and reproduce become extinct. Fossils represent the remains of plants and animals, including some that are extinct. Many extinct plants and animals looked something like plants and animals that are alive today, while others were very different from anything alive today. This topic engages students in looking closely at plants and animals and noticing similarities and subtle differences. It also lays the foundation for later study of Evolution and of Earth History.