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# Becoming Familiar with SI

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### 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"...

### Nanotechnology - learn about the very small.

Credit: Pixabay
• 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).
• Nanotechnology - NIST and Nanosoccer (NIST). Explore how nanosoccer worked and how its lessons helped pave a path toward working microrobots.
• 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 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!

## Contacts

• Metric Program
Created April 13, 2010, Updated August 13, 2024