Balloons and Static Electricity

Contributor
PhET Middle School Team
Type Category
Instructional Materials
Types
Simulation , Lesson/Lesson Plan , Activity
Note
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.

Reviews

Description

Students investigate the actions of charged balloons.  They then use the PhET simulation “Balloons and Static Electricity” to make sense of their observations in the light of electric charge, and the simulation “Electric Field Hockey” to apply their understanding of electric charge.  The lesson plan includes a pre-test and a post-test as well as an activity guide for the students. (To see the entire lesson plan, in order, choose the “BalloonsAndCharges_MS_all_pages” doc or PDF).

Intended Audience

Educator and learner
Educational Level
  • Grade 8
  • Grade 7
  • Grade 6
  • Middle School
Language
English
Access Restrictions

Free access with user action - The right to view and/or download material without financial barriers but users are required to register or experience some other low-barrier to use.

Performance Expectations

MS-PS2-3 Ask questions about data to determine the factors that affect the strength of electric and magnetic forces.

Clarification Statement: Examples of devices that use electric and magnetic forces could include electromagnets, electric motors, or generators. Examples of data could include the effect of the number of turns of wire on the strength of an electromagnet, or the effect of increasing the number or strength of magnets on the speed of an electric motor.

Assessment Boundary: Assessment about questions that require quantitative answers is limited to proportional reasoning and algebraic thinking.

This resource is explicitly designed to build towards this performance expectation.

Comments about Including the Performance Expectation
The activity set builds to a culminating question in which students explain their ideas about whether two objects will attract or repel, and how strongly they will do so. The lesson could incorporate students’ asking their own questions, by having students share not only what they observe, but also what they wonder, during the activity with real balloons. Those questions could be used as a launching point for the simulation investigations that follow.

Science and Engineering Practices

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
Students make observations of the behaviors of charged balloons, a simulated balloon/wall/sweater system, and simulated “charged” hockey pucks, in order to construct an explanation about how attracting and repelling work. They are specifically asked to write “rules” that explain the speed of a charged object, and an explanation of a method for moving a charged object. They are also asked throughout the lesson to use their new observations to support, revise, or add to their earlier explanations. Students will likely need another source, such as a background reading, to make sense of what the “pluses” and “minuses” are in the simulations, and where they come from.

Disciplinary Core Ideas

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
The purpose of the lesson is for students to construct ideas about attraction and repulsion based on electric charge. The influence of charge magnitude is specifically referenced in the activity questions for both simulations, which ask students about objects sticking weakly vs. strongly, and about how to make charged objects move more quickly or more slowly.

This resource appears to be designed to build towards this disciplinary core idea, though the resource developer has not explicitly stated so.

Comments about Including the Disciplinary Core Idea
Although the lesson focuses more on the idea of the strength of charges, the actions of the objects in the activity and simulations are also influenced by the existence of fields. A teacher could use this lesson first, and one about fields later, referring back to or revisiting the actions of the balloon and the pucks with respect to fields.

Crosscutting Concepts

This resource is explicitly designed to build towards this crosscutting concept.

Comments about Including the Crosscutting Concept
The purpose of the lesson’s referenced simulations is to act as models showing microscopic particles, to help students understand the actions of macroscopic objects (charged balloons). The students are likely to need background knowledge, or supporting text, to help them understand that the “pluses and minuses” in the simulations are electric charges, based on the buildup or discharge of electrons which are themselves too small to see.

Resource Quality

  • Alignment to the Dimensions of the NGSS: The lesson begins with exploration of a phenomenon (charged balloons). Students then use the cross-cutting concept of scale to investigate core ideas about electric charge, and are asked to use the practice of constructing explanations, to share their findings. Note that the lesson is about electric charge only, not magnetism or gravity, so it does not on its own fully address the core ideas or Performance Expectation.

  • Instructional Supports: The lesson begins with an entry point familiar to many - rubbing balloons on hair. Students are asked to revise, change, and/or add to their thinking about charges as they progress through the sequence of activities and simulations. The sequence guides them through an opportunity to gather knowledge, followed by an opportunity to apply that knowledge, then to explain why their ideas work. The lesson is not clear about where it would fit in an NGSS progression, nor does it give suggestions for differentiation.

  • Monitoring Student Progress: The lesson includes a pre-test and a post-test, which address ideas from the DCI, and ask students to construct explanations from given information and diagrams, but do not address a CCC. Student discussions, answers to activity guide questions, and especially the questions that ask students to revise, add to or support their original ideas, serve as useful formative assessments. Answer keys are not provided.

  • Quality of Technological Interactivity: The Balloons and Electric Charge PhET model is intuitive and simple to interact with. It uses HTML5. The Electric Field Hockey interface is more complicated, and while this gives many options for interactivity, it is not as immediately user-friendly. Students may need a demonstration of how to use this simulation. The Electric Field Hockey simulation requires Java.