Alaska Science Key Element A6 A student who meets the content standard should understand that forces of nature cause different types of motion, and describe the relationship between these forces and motion (Motion).
 Performance Standard Level 1, Ages 5–7 Students observe and record changes in an object’s position and motion when applying a push or pull. Sample Assessment Ideas Students describe or demonstrate the pushes or pulls that can be used to move an object through a simple maze. Students explain the motions of a balance or teeter-totter in terms of the “weight” of objects placed on it. Expanded Sample Assessment Idea Students build a game where marbles collide; measure the distance and direction (angle) of marbles that have collided.
 Procedure Students will: Cut a piece of paper large enough to fit snugly, yet lie flat, in the bottom of the tray. Remove the paper from the tray. Fold a 12-inch diameter circle in half and firmly press the edge of the fold; fold in quarters, eighths and sixteenths; open the circle; refold along the same lines but in the opposite direction to help flatten the folds so they do not curl the edge of the circle. Put the circle in the middle of the tray paper; hold the circle flat with one hand and mark a dot on the tray paper each place a fold touches the tray paper; connect the opposite dots to create a design similar to this: * (Each student should prepare one of these forms but can use teacher prepared tray papers for their additional trials.) Put the tray paper back in the tray. Place one marble in the tray at the center crossing point; place a second marble at the edge of the tray along another of the lines. Mark the starting position of the second marble. Carefully roll the second marble so that it collides with the first marble. Mark the position of both marbles when they stop; remove the marbles from the tray. Use a marking pen to draw and label the path of each marble. Measure how far each marble went. Repeat steps 4–10 using a new tray paper but keep the same position for the second marble. Repeat steps 4–11 using a new starting position for the second marble. Repeat steps 4–11 using a variety of marbles (2 large, 1 large and 1 small, marbles made of different materials, and so on). Compare the results with others in class. Reflection and Revision What caused the first marble to move after the collision? Did the repeat marble collision always get the same results as the first collision? What would happen if the two marbles were not the same size? If the marbles were not made of the same material? How can you tell how much push you gave to the second marble to start it moving? How could you change the game so that every marble got the same amount of push to start it moving? When you examine the class results, is there a pattern to the motion for different marbles? Levels of Performance Stage 4 Student work is complete and shows detailed evidence of the transfer and extension of knowledge related to how a push or pull changes the position or motion of an object. The student creates at least four complete sets of marble path diagrams that are clearly labeled, tests several marble variations (size, material, starting position), and always includes the repeat experiment. The student examines class data, identifies and explains patterns of motion for different marbles, and designs a method to deliver a uniform push for each marble roll. Stage 3 Student work is complete and shows some evidence of the transfer or extension of knowledge related to how a push or pull changes the position or motion of an object. The student creates at least two sets of marble path diagrams that are labeled, tests several marble variations (size, material, starting position), and includes the repeat experiment although aspects of the diagrams may be unclear. The student examines class data, identifies patterns of motion for different marbles, and designs a method to deliver a similar push for each marble roll. Stage 2 Student work may be incomplete and show little evidence of knowledge related to changes in the position or motion of an object. The student creates marble path diagrams that are incomplete or lack labels. The student may attempt to design a method to deliver a similar push for each marble roll. Stage 1 Student work is mostly incomplete and contains misconceptions related to the position or motion of an object. Marble path diagrams, if included, are incorrect or not labeled. Attempts to design a method to deliver a push for each marble roll may be inappropriate to the game or not work.
 Standards Cross-References ( Alaska Department of Education & Early Development Standards) National Science Education Standards The position of an object can be described by locating it relative to another object or the background. (Page 127) An object’s motion can be described by tracing and measuring its position over time. (Page 127) The position and motion of objects can be changed by pushing or pulling. The size of the change is related to the strength of the push or pull. (Page 127) Benchmarks Things move in many different ways, such as straight, zigzag, round and round, back and forth, and fast and slow. (Page 89) The way to change how something is moving is to give it a push or a pull. (Page 89)