Grade Two Science Strand Motion, and Energy This strand focuses on student understanding of what force, motion, and energy are and how the concepts are connected. The major topics developed in this strand include magnetism, types of motion, simple and compound machines, and energy forms and transformations, especially electricity, sound, and light. This strand includes science standards K.3, 1.2, 2.2, 3.2, 4.2, 4.3, 5.2, 5.3, 6.2, and 6.3.
2.3 The student will investigate and understand basic properties of solids, liquids, and gases. Key concepts include a) identification of distinguishing characteristics of solids, liquids, and gases; b) measurement of the mass and volume of solids and liquids; and c) changes in phases of matter with the addition or removal of energy. Overview This standard continues to focus on matter. In 2.3 students build upon the knowledge introduced in K.4 and 1.3. In K.4 physical properties of matter are investigated and the properties of water are observed and tested. In 1.3 students investigate how common materials interact with water. In 2.3 students investigate, by conducting simple experiments, the properties of solids, liquids, and gases. It is intended that students will actively develop and utilize scientific investigation, reasoning, and logic skills (2.1) in the context of the key concepts presented in this standard.
2.3 The student will investigate and understand basic properties of solids, liquids, and gases. Key concepts include a) identification of distinguishing characteristics of solids, liquids, and b) measurement of the mass and volume of solids and liquids; and c) changes in phases of matter with the addition or removal of energy. Understanding the Standard (Background Information for Instructor Use Only) Essential Knowledge, Skills, and Processes All substances are made of matter. Matter is anything that has mass and takes up space. Solids have a defined shape and volume. Liquids have a definite volume and take the of the container. Gases will completely fill any closed container (take the shape of its container) and assume the volume of its container. (e.g., Helium gas put into a balloon takes the shape of the balloon because the balloon defines its shape.) Mass is a measure of the amount of matter. Weight is the measure of the gravitational pull on an object. Volume is the measure of the amount of space occupied by matter. Matter most commonly occurs in phases: solids, liquids, and gases. Matter can change from one phase to another. When matter changes from one phase to another, these changes are referred to as physical changes. Changes from solid to liquid to gas require the addition of energy. In order to meet this standard, it is expected that students will classify materials as to whether they are liquids, solids, or describe and identify examples of condensation, evaporation, melting, and freezing of water. measure the mass of solids and the volume of liquids in metric and standard English units. examine and describe the transformation of matter from one phase to another, i.e., solid water (ice) to liquid (water) to gas (water vapor). conduct an investigation to observe the condensation of water. design and conduct an investigation to determine basic factors that affect the evaporation of water. identify the phases of water and the uses of water in its various phases in the home and at school.
Land surfaces are subject to the agents of weathering and erosion. Land surfaces that are not covered with or protected by plants are more likely to be subject to the loss of soil by wind and water. Weathering is the breaking down of rocks, which usually happens over long periods of time. Erosion is the process by the products of weathering are moved from one place to another. Erosion may happen quickly (e.g., during a flood or a hurricane) or over a long period of time.