Unit Plan 6 (Grade 8 Math): Operating with Scientific Notation
8th graders learn to multiply, divide, add, and subtract numbers in scientific notation, normalize results, and interpret outcomes with correct units and scale. This weeklong math unit builds precision, fluency, and real-world understanding of large and small quantities.
Focus: Perform operations with numbers in scientific notation and interpret results in context (scale, units).
Grade Level: 8
Subject Area: Mathematics (Expressions & Equations)
Total Unit Duration: 5 sessions (one week), 45–60 minutes per session
I. Introduction
This week students operate with scientific notation and use results to make sense of real-world scale and units. They will multiply, divide, add, and subtract numbers written in scientific notation (and standard form), then normalize results (1 <= a < 10) and interpret them with appropriate units and orders of magnitude. Technology outputs like 3.2E5 will be read and rewritten clearly.
Essential Questions
- How do I multiply, divide, add, and subtract numbers written in scientific notation efficiently and accurately?
- How do I normalize results so the coefficient stays in the range 1 <= a < 10?
- How do I choose units (meters vs kilometers, micrometers vs meters) so answers are easy to read and make sense?
II. Objectives and Standards
Learning Objectives — Students will be able to…
- Multiply and divide numbers in scientific notation by operating on coefficients and exponents, then normalize results.
- Add and subtract numbers in scientific notation by aligning exponents or converting to standard form as needed.
- Interpret technology notation (for example, 7.5E-3) and select appropriate measurement units for very large/small answers.
- Explain solutions with precision (units, coefficient/exponent correctness, reasonableness checks).
Standards Alignment — CCSS Grade 8
- 8.EE.4: Perform operations with numbers expressed in scientific notation, including problems where both decimal and scientific notation are used. Use scientific notation and choose units of appropriate size for very large or very small measurements; interpret scientific notation generated by technology.
Success Criteria (student-friendly)
- I can compute (2.4 * 10^3) * (5 * 10^-2) and write the result in proper scientific notation.
- I can add 6.1 * 10^5 and 8.3 * 10^4 by aligning exponents and justify each step.
- I can read technology output like 1.2E7 as 1.2 * 10^7 and explain what it means with units.
- I can choose a better unit (for example, km^2 instead of m^2) so the number is readable and the exponent reflects the scale.