Becoming Familiar with SI

The SI (metric system) is easy to use! Learn everyday SI reference points

Learning the SI (International System of Units, commonly known as the metric system) requires developing just a few reference points - a general indicator you can use to orient yourself. Reference points help build that innate understanding of "how much." The metric system is a complete measurement system made up of 7 base units. Once you are familiar the SI basics you are ready to go! HINT: Learning the SI is not about making unit conversions in your head (this will only slow you down). Check out these resources to learn to "think metric"...

• NIST Metric Trivia Quiz
  • How much do you know about the metric system (SI)? Try the NIST Metric Trivia Quiz online or use the Alexa skill to test your knowledge and be on your way to thinking metric!
• How Big are Things Cube (Vendian).
• Size and Scale (University Wisconsin-Madison).  Resources help learn approximate size and scale of things.
• Orders of Magnitude - Distance (Francis).
• The Electromagnetic Spectrum (NASA) PDF
• Metric Scales in Geology:
  • Sediment - Wentworth Grade Scale PDF. (U.S. Geological Survey). This chart can be used to grade sediment particles by size.
  • Measuring Fossils (The Paleontological Society) - Students practice their skills estimating and measuring fossil lengths.
  • Observing Fossils (The Paleontological Society) - Students practice their observing skills.
• Worlds Tallest High-rise Buildings (Emporis).
• Tallest Trees in North America (Monumental Trees).
• U.S. Temperature Map Celsius (Weather Central).

Simulations and tutorials help students explore successive orders of magnitude.

• Scale of the Universe (Huang and Martori).
• Secret Worlds: The Universe Within (Florida State University).
• Universcale (Nikon).
• NanoKids - Explore (Rice University). Available in Spanish.
• Powers of Ten (Eames).
• The Cosmic Distance Scale (NASA).
• Planetary Fact Sheet (NASA).
• The World’s Smallest Devices - Technology Size Comparison (Branch Education).

Nanotechnology - learn about the very small.

• Scale of Things - Nanometers (U.S. Department of Energy). Check out this chart and discover the scale of things for super small natural and synthetic items from the nano world!
• The Size of Nanoscale. (National Nanotechnology Initiative). These examples can help you understand just how small a nanometer is (one-billionth of a meter).
• What is Nanoscale? (University of Wisconsin-Madison). Try out this activity to see how everyday objects compare to the nanoscale.
• How the Nanoscale Measures Up (National Geographic Society). Hands-on activities help students explore the nanoscale and how it compares to the macro and micro scales.  Incorporate mathematics and visual media.
• How Small is Nano? (Video – NISE). What is a nanometer? What things are measured in nanometers? This video explores the macro, micro, and nano scale. Available in Spanish.
• How Small is Nanotechnology? (Lawrence Hall of Science). Explore these activities to learn how scientists measure at the nanoscale.
• How Small is Small (Lesson Plan) – What is a Microorganism? (NPS – Zion NP).  Students conceptualize the size of microorganisms by using a large scale model of specific organisms.
• Explore the World of the Small: Measuring in Nanometers (Smithsonian).  Students (grade 7 and 8) become aware of the relative size of a nanometer and discover some objects that are measured in this unit.  
• The Micro and Macro Worlds (NNIN) This activity focuses on scale and the importance of using scale bars when presenting nanoscale structures.
• SI System and Nanoscale Science (National Nanotechnology Coordinated Infrastructure).
• The Metric System from Big to Small (National Nanotechnology Coordinated Infrastructure). Relate the size and scale of objects to various metric units.
• Size and Scale Poster (National Nanotechnology Coordinated Infrastructure). Learn about the very small.
• How Big Is It? (Stanford University). This activity introduces students (grade 2 and 4) to the nanoscale using the metric system.
• How Big is a ...? (Cells Alive). This animation compares the relative sizes of cells and organisms.
• Relative Sizes and Detection Devices (Florida State University).
• How Small is Small? (Lawrence Hall of Science). Play a game! Can you arrange these objects from smallest to biggest? Sure, it's fun!

Resources

• Understanding Metric
• SI Basics
• Prefixes
• Everyday Estimation

• Writing with Metric Units

• Unit Conversion

• National Metric Week

• Metrication FAQ

• SI Publications

• SI Education and Training

• SI Teacher Kit

• SI Professional Development

• NIST Education Resources

• NEST-R (STEM Registry)