The Measurement League: Guardians of the S.I.

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

  • Running Out of Time! | SI Superheroes

    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".

    Grades: 4-6, 8
  • Mass Hysteria | SI Superheroes

    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.

    Grades: 4-6