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Webinar: Notice of Funding Opportunity: High School Curricula Materials that Reflect the SI Redefinition

Note: Captioning will be available by 12/17.


NIST invites applications from eligible applicants for the development, production and distribution of science and/or mathematics curricula resources for high school classrooms that reflect the recent redefinition of units within the international system of measurement (also called the metric system or SI).

Over the course of the twentieth century, technology advances in industry and scientific research have demanded increasingly precise measurements. As a result, the definitions for some metric units of measurement have been updated from being based on physical objects to being based on immutable natural constants.

For example, in 1967, the second was redefined to be the duration of 9,192,631,770 cycles of the radiation of the cesium-133 atom as it oscillates from one energy level to another. And in 1983, the length of a meter was redefined as the distance light travels in vacuum in 1/299,792,458 of a second. The kilogram and the measurement units derived from it, however, will no longer be determined by a single small cylinder of platinum-iridium stored in a vault outside of Paris.

After many years of work, scientists have redefined the kilogram, the last remaining base unit of measure based on an artifact. On November 16, 2018, at an event held at the Palace of Versailles in France, a committee of the International Bureau of Weights and Measures endorsed a revised SI system of measurement based entirely on the natural world and the laws of physical science.


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Created November 27, 2018, Updated July 23, 2020