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SI Superheroes Videos

Emerging from their environmentally shielded world headquarters at NIST, the SI superheroes are dedicated to the fight against uncertainty, imprecision and inaccuracy and to improving the quality of our lives and the things we build.

Episode 5: Late Notice

League of SI Superheroes, Episode 5: Late Notice
League of SI Superheroes, Episode 5: Late Notice
When Rebecca oversleeps and sets the morning spiraling into chaos, she accidentally uncovers her mom’s biggest secret. What begins as a scramble to catch the school bus becomes an epic journey through the history of timekeeping—from sundials to atomic clocks. But as Professor Second reveals the wonders of precise time measurement, Major Uncertainty lurks in the background, ready to throw everything off balance. Packed with heart, humor, and scientific discovery, this short animation is a time-bending adventure for all ages. More Info: https://www.nist.gov/kids

Episode 4: Two Truths and a Lie

League of SI Superheroes, Episode 4: Two Truths & a Lie
League of SI Superheroes, 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". More info at www.nist.gov/kids

Episode 3: Mass Hysteria

League of SI Superheroes, Episode 3: Mass Hysteria
League of SI Superheroes, Episode 3: Mass Hysteria
The nefarious Major Uncertainty has kidnapped Monsieur Kilogram, putting the world’s measurements of mass in jeopardy. As the world spirals into Mass Hysteria, the remaining SI Superheroes, champions of the metric system, leap into action to save the day, and hopefully Monsieur Kilogram as well.

Episode 2: Running Out of Time!

League of SI Superheroes, Episode 2: Running Out of Time!
League of SI Superheroes, Episode 2: Running Out of Time!
In their second suspenseful adventure, the League of SI Superheroes battle archvillain Major Uncertainty in a race to keep the world's satellite navigation system "on time".

Episode 1: Desperate Measures!

League of SI Superheroes, Episode 1: Desperate Measures!
League of SI Superheroes, Episode 1: Desperate Measures!

 

Created August 1, 2022, Updated May 20, 2025
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