Unit 2 — Pushes and Pulls
Description
Students apply understanding of the effects of different strengths or different directions of pushes and pulls on the motion of an object to analyze a design solution. The crosscutting concept of cause and effect is called out as the organizing concept for this disciplinary core idea. Students demonstrate grade-appropriate proficiency in planning and carrying out investigations and analyzing and interpreting data. Through hands-on investigations, students discover that pushes and pulls can have different strengths and directions, can change speed and direction of motion, and can start or stop an object. Students engage in a portion of the engineering design process to determine whether a design solution works as intended to change the speed or direction of an object. Because there is always more than one possible solution to a problem, students compare and test designs. This unit is based on K-PS2-1, K-PS2-2, and K-2-ETS1-3.
Essential Questions
- What does science have to do with playing sports?
- Why do scientists like to play soccer?
- How can you design a simple way to change the speed or direction of an object using a push or pull from another object?
Learning Objectives
- Plan and conduct an investigation to compare the effects of different strengths or different directions of pushes and pulls on the motion of an object.
- Analyze data to determine if a design solution works as intended to change the speed or direction of an object with a push or a pull.
- Analyze data from tests of two objects designed to solve the same problem to compare the strengths and weaknesses of how each performs.
Supplemental Resources
- Push Pull-Changing Direction (OER) - Students investigate interactions between colliding objects using pushes and pulls through kickball observations
- Marble Roll (NSTA) - Assessment probe from Uncovering Student Ideas in Primary Science Vol. 1 to elicit descriptions of motion
- Roller Coaster (More Picture Perfect Science Lessons, NSTA Press) - Students explore changing speed and direction by building roller coasters from pipe insulation
- Ramps 2: Ramp Builder (OER) - Multi-day lesson plan where students design, build, and test their own ramps
- Balls, toy cars, pull toys, cans, tops, and boxes for push and pull investigations
- Ramps made from cardboard, paper tubes, rubber bands, and foam
- Markers for labeling and recording observations
- Graphic organizers for data collection from investigations
Engineering, Technology, and Applications of Science
Physical Sciences
Students engage in ELA literacy practices across all five science units. They ask and answer questions about key details in informational texts, participate in shared research and writing projects, compose informative and opinion pieces using drawing, dictating, and writing, add visual displays to descriptions, and use speaking and listening skills to seek information and clarify understanding in the context of science investigations.
Students apply mathematics practices and measurement standards throughout the science units. They reason abstractly and quantitatively, model with mathematics, use appropriate tools strategically, describe and compare measurable attributes of objects, classify and count objects into categories, and know number names and the count sequence to analyze and represent data from science investigations.
Formative Assessments
- With guidance, design simple tests to gather evidence to support or refute ideas about cause-and-effect relationships.
- With guidance, plan and conduct an investigation in collaboration with peers to compare effects of different strengths or different directions of pushes and pulls on the motion of an object.
- Analyze data from tests of an object or tool to determine if it works as intended.
- Analyze data from tests of two objects designed to solve the same problem to compare the strengths and weaknesses of how each performs.
- Analyze data to determine whether a design solution works as intended to change the speed or direction of an object with a push or a pull.
Summative Assessment
Students create a game using pushes and pulls that meets specified design criteria, such as moving an object a certain distance or along a particular path.
Benchmark Assessment
— not configured —
Alternative Assessment
Students use ramps at different angles to demonstrate the effect on speed and distance traveled, or use physical characteristics of animals to match them to the appropriate habitat.
IEP (Individualized Education Program)
During hands-on investigations with pushes and pulls, provide physical guidance or partner support to help students execute force-based tasks and verbalize their observations rather than relying on written recording. Use picture-supported data collection tools — such as simple charts with images of objects moving fast or slow, near or far — so students can point or stamp to indicate results. When comparing the effects of different forces, break the investigation into small, clearly sequenced steps with visual cues at each stage, and allow students to demonstrate understanding by showing, acting out, or dictating their findings to an adult.
Section 504
Ensure students have preferential positioning during group investigations so they can clearly observe and participate in push-and-pull demonstrations without distraction. Allow additional time during data collection and comparison tasks, and provide a quiet or low-distraction space when students are asked to analyze results and share conclusions about force and motion.
ELL / MLL
Build key vocabulary — such as push, pull, fast, slow, direction, and strength — using real objects, gestures, and picture-word cards that students can reference throughout the unit's investigations. Provide simplified, visual directions for each step of force-and-motion explorations, and encourage students to describe what they observe using their home language before transitioning to English scientific vocabulary.
At Risk (RTI)
Begin force-and-motion investigations with familiar, concrete scenarios — such as rolling a ball or sliding a block — to activate prior physical experience before introducing scientific vocabulary and comparison tasks. Reduce the number of variables students track at one time, focusing first on one type of force (push or pull) or one outcome (faster or slower), and use visual anchors and sentence frames to help students communicate cause-and-effect observations with growing confidence.
Gifted & Talented
Invite students to move beyond testing a single variable by exploring how combining different strengths and directions of force affects an object's path, and to generate their own questions for investigation during the engineering design phase. When designing their push-and-pull game, challenge students to establish and test multiple design criteria, consider trade-offs between their design choices, and explain their reasoning for why one solution performs better than another using evidence from their tests.