Curated OER
States Quizzes
In this state postal code worksheet, students respond to 45 fill in the blank questions that require them to use the listed state postal codes as answers.
National Council of Teachers of Mathematics
Nctm: Figure This: Bar Codes
An exploration of the binary system using U.S. postal zip codes. Discover what numbers the long and short bars in a zip code represent in this one page activity from the NCTM Math Challenges for Families collection.