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# SI Measurement System Chart

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 Keywords: SI, metric system, base unit, kilogram, kelvin, meter, candela, second, ampere, mole, international Audience: Students, Parents, Educators, General Public, Technology Coordinators, Outreach Ambassadors Grade Level: 3 to Higher Education Subjects: SI units, research at NIST: metrology

### Summary

This resource provides a colorful printable SI system chart, which displays the 7 SI base unit, prefix symbols, and features the Measurement League: Guardians of the SI superheroes, dedicated to the fight against uncertainty, imprecision, and inaccuracy and to improving the quality of our lives and the things we build. The superheroes include the following: Mole, Professor Second, Monsieur Kilogram, Ms. Ampere, Dr. Kelvin, Meter Man, and Candela. SI Prefix symbols featured in the chart are used to represent smaller or larger units by factors that are powers of 10. The chart provides an entertaining way to learn more about the International System of Units (SI). NOTE: Four new International System of Units (SI) prefixes (ronna, ronto, quetta, and quecto) were adopted in November 2022 and are not currently represented in this publication.

The chart may be printed on any paper size but is recommended to be at minimum 215.9 mm x 279.4 mm (8.5 in x 11 in).

### Learning Objectives

• Understand SI base units of measure
• Learn metric prefixes
• Recognize the definitions of base units

### Materials

• Required
• Digital file
• Paper
• Printer
• Recommended
• 215.9 mm x 279.4 mm (8.5 in x 11 in) size paper

### Safety

Use caution when handling paper edges to prevent injury.

### Teaching Tips

Explain the SI base units, unit definitions, and metric prefixes. State each base unit depends upon a defining constant. Additionally, mention the combination of SI base units creates the SI derived units. Hardcopy charts are available while supplies last. Contact the NIST Metric Program at TheSI [at] nist.gov and include your name and U.S. mailing address.

### Classroom Connections

• Videos. Comic book-style video animations, available on the NIST YouTube Channel.
• Episode 4: Two Truths & a Lie. After rescuing Monsieur Kilogram and capturing Major Uncertainty, our Superheroes take a break and play a game of "Two Truths & a Lie."
• Episode 3: Mass Hysteria! The nefarious Major Uncertainty has kidnapped Monsieur Kilogram, putting the world’s measurements of mass in jeopardy.
• Episode 2: Running Out of Time! The SI Superheroes battle archvillain Major Uncertainty in a race to keep the world's satellite navigation system "on time."
• Episode 1: Desperate Measures! The SI Superheroes use the power of measurement to help a stranded soccer player get home.
• Companion Resources:
• SI Units
• SI Redefinition Constants
• Redefining the World’s Measurement System
• SI Prefixes
• SP 1247 SI Relationships Poster