OpenSciEd Unit 7.1 · Lesson 06 · 6.A
Explaining Another Phenomenon
Assessment guide
How to read student work on this assessment — standards alignment, what strong understanding looks like, and common gaps.
Learning progression
Target understanding
6.A Apply key model ideas and patterns in mass and property data to construct three explanations for: a) why the mass of a system decreases when substances are mixed together (potassium iodide and hydrogen peroxide), b) which substance(s) could or could not be produced in that process, and c) what additional tests could be done on the gas (or other gases) to help identify additional substances that aren’t being produced in this process.
Standards alignment
6.A Apply key model ideas and patterns in mass and property data to construct three explanations for: a) why the mass of a system decreases when substances are mixed together (potassium iodide and hydrogen peroxide), b) which substance(s) could or could not be produced in that process, and c) what additional tests could be done on the gas (or other gases) to help identify additional substances that aren’t being produced in this process.
What understanding looks like
Strong
- Use Elements to look for in students’ written arguments for guidance on what to look for in their written argument. Use this guidance to provide feedback to students on their written arguments.
From Teacher Edition
View assessment opportunity →Facilitation guidance from the lesson plan — what to notice in student thinking and how to respond while teaching.
Building towards
6.A Apply key model ideas and patterns in mass and property data to construct three explanations for: a) why the mass of a system decreases when substances are mixed together (potassium iodide and hydrogen peroxide), b) which substance(s) could or could not be produced in that process, and c) what additional tests could be done on the gas (or other gases) to help identify additional substances that aren’t being produced in this process.
What to look / listen for
Use Elements to look for in students’ written arguments for guidance on what to look for in their written argument. Use this guidance to provide feedback to students on their written arguments.
What to do
For students who need additional scaffolding for the written argument, use Alternate: Explaining another phenomenon that has sentence starters and other supports for students.
Materials
Last updated from official OpenSciEd on 7/1/2026
Student handout
7.1 Lesson 6 Assessment Explaining Another Phenomenon.docx
Google Form
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Teacher guide
7.1 Lesson 6 Teacher Edition.docx
Answer key (recommended)
7.1 Lesson 6 Answer Key Elements to look.docx