Explain their own ideas and understanding in light of the discussion.
Divide students into two groups. One group should read about Sir Isaac Newton and the other group should read about Galileo Galilei. Students should come to class prepared to discuss how their scientist is more important to the understanding of gravity than the other.
Measure and estimate liquid volumes and masses of objects using standard units of grams (g), kilograms (kg), and liters (l). Add, subtract, multiply, or divide to solve one-step word problems involving masses or volumes that are given in the same units, e.g., by using drawings (such as a beaker with a measurement scale) to represent the problem.
Read about the difference between mass and weight on earth from the facts page of Science Trek's Gravity site. Gather a variety of objects from your class and measure both their weight and their mass. Compare how they are different. Create a chart to show each of the measurements for all the objects.
Use the four operations to solve word problems involving distances, intervals of time, liquid volumes, masses of objects, and money, including problems involving simple fractions or decimals, and problems that require expressing measurements given in a larger unit in terms of a smaller unit. Represent measurement quantities using diagrams such as number line diagrams that feature a measurement scale.
Evaluate expressions at specific values of their variables. Include expressions that arise from formulas used in real-world problems. Perform arithmetic operations, including those involving whole-number exponents, in the conventional order when there are no parentheses to specify a particular order (Order of Operations). For example, use the formulas V = s³ and A = 6s² to find the volume and surface area of a cube with sides of length s = ½.
Using the following NASA StarChild page, enter your weight on earth. Then, calculate a formula for determining your weight on three different planets in our solar system.
Plan and conduct an investigation to provide evidence of the effects of balanced and unbalanced forces on the motion of an object.
Each force acts on one particular object and has both strength and a direction. An object at rest typically has multiple forces acting on it, but they add to give zero net force on the object. Forces that do not sum to zero can cause changes in the object's speed or direction of motion. Assessment is limited to gravity being addressed as a force that pulls objects down.
Make observations and/or measurements of an object's motion to provide evidence that a pattern can be used to predict future motion.
Force applied to an object can alter the position and motion of that object: revolve, rotate, float, sink, fall, and at rest. The patterns of an object's motion in various situations can be observed and measured; when that past motion exhibits a regular pattern, future motion can be predicted from it.
Support an argument that the gravitational force exerted by Earth on objects is directed down.
The gravitational force of Earth acting on an object near Earth's surface pulls that object toward the planet's center. "Down" is a local description of the direction that points toward the center of the spherical Earth.
Construct and present arguments using evidence to support the claim that gravitational interactions are attractive and depend on the masses of interacting objects.
Gravitational forces are always attractive. There is a gravitational force between any two masses, but it is very small except when one or both of the objects have large mass-e.g., Earth and the sun. Examples of evidence for arguments could include data generated from simulations or digital tools; and charts displaying mass, strength of interaction, distance from the Sun, and orbital periods of objects within the solar system.
Conduct an investigation and evaluate the experimental design to provide evidence that fields exist between objects exerting forces on each other even though the objects are not in contact.
Forces that act at a distance (electric, magnetic, and gravitational) can be explained by fields that extend through space and can be mapped by their effect on a test object. Examples of investigations could include first-hand experiences or simulations.
Develop and use a model of the Earth-sun-moon system to describe the cyclic patterns of lunar phases, eclipses of the sun and moon, and seasons.
Patterns of the apparent motion of the sun, the moon, and stars in the sky can be observed, described, predicted, and explained with models. The solar system consists of the sun and a collection of objects held in orbit around the sun by its gravitational pull of them. This model of the solar system can explains eclipses of the sun and the moon. Earth's spin axis is fixed in direction over the short-term but tilted relative to its orbit around the sun, resulting in the seasons.
Develop and use a model to describe the role of gravity in the motions within galaxies and the solar system.
The solar system consists of the sun and a collection of objects, including planets their moons, and asteroids that are held in orbit around the sun by its gravitational pull on them. Our solar system appears to have formed from a disk of dust and gas, drawn together by gravity. Emphasis for the model is on gravity as the force that holds together the solar system and Milky Way galaxy and controls orbital motions within them. Examples of models can be physical (such as computer visualizations of elliptical orbits) or conceptual (such as mathematical proportions relative to the size of familiar objects.)