Short Performance Assessment- Road Runner Ice Melt- Electrical Forces between Particles

The Wonder of Science
Type Category
Assessment Materials
Assessment Item
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.



This resource is a short performance assessment, adapted from Stanford University’s SNAP project to provide NGSS- aligned assessment on HS-PS1-3. Students are given a scenario, where they have to find out the best salt to prevent ice from forming on the wintery roads. Students plan and conduct an investigation using five different substances to find out the best substance to prevent ice from forming Then they explain the best substance based on the patterns of the properties which stem from the strength of electrical forces between particles. At the end of this performance assessment task, students are assessed with grading rubrics for designing and conducting the experiment and taking appropriate data and on the rationale for  the choice of their material based upon the properties and the strength of electrical forces between the particles

Intended Audience

Educator and learner
Educational Level
  • High School
Access Restrictions

Free access - The right to view and/or download material without financial, registration, or excessive advertising barriers.

Performance Expectations

HS-PS1-3 Plan and conduct an investigation to gather evidence to compare the structure of substances at the bulk scale to infer the strength of electrical forces between particles.

Clarification Statement: Emphasis is on understanding the strengths of forces between particles, not on naming specific intermolecular forces (such as dipole-dipole). Examples of particles could include ions, atoms, molecules, and networked materials (such as graphite). Examples of bulk properties of substances could include the melting point and boiling point, vapor pressure, and surface tension.

Assessment Boundary: Assessment does not include Raoult’s law calculations of vapor pressure.

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

Comments about Including the Performance Expectation
This Short Performance Assessment (SPA) covers the PE entirely. One suggestion as an extension activity could be have students contact the city (if it snows in their city) to see what they actually use to melt ice and compare other facets such as cost effectiveness and environmental safety.

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 plan and conduct the investigation, decide which data to collect to find the best salt to prevent ice from forming and then use the data as evidence to make the claim for the best salt to solve this problem.

Disciplinary Core Ideas

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

Comments about Including the Disciplinary Core Idea
This assessment addresses this DCI by having students connect the patterns in the macro property of electrical conductivity to the electrical forces between particles. Students will measure the conductivity of different substances in solution and will relate that higher conductivity means more number of particles. Then, based upon the prior knowledge of colligative properties, students will be able to predict that the substance with highest conductivity will be the best substance to melt the ice because of most lowering of freezing point.

Crosscutting Concepts

This resource appears to be designed to build towards this crosscutting concept, though the resource developer has not explicitly stated so.

Comments about Including the Crosscutting Concept
While this resource addresses electrical conductivity as a measure for effectiveness in preventing icy roads, the reason for this connection could be further strengthened with the concept of colligative properties and freezing point depression. Developing the rubrics further will provide more guidance in terms of the goals of assessment of this resource.

Resource Quality

  • Alignment to the Dimensions of the NGSS: This Short Performance Assessment is a quality resource that aligns well all three dimensions of NGSS. This resource challenges students with a performance task, where they engage in planning and carrying out investigation to look for patterns in the electrical conductivity for the best salt to prevent ice from forming on the wintry roads. Students further connect the macroscopic property of conductivity with microscopic electrostatic interactions.

  • Instructional Supports: This resource would benefit from a teacher guide and sample student work to show how it can be implemented. Teachers must decide upon their rubric prior to students being evaluated using this assessment tool.

  • Monitoring Student Progress: This is an assessment tool for HS-PS1-3 hence monitoring student progress is not applicable.

  • Quality of Technological Interactivity: This assessment does not use technological interactivity.