Curated OER
Math Shortcuts
Looking for a different way to introduce long division? Need a shortcut for checking multiplication answers? Then this is for you! The multiplication method uses a quick trick to check for accuracy. The division method allows learners to...
Curated OER
Clock Arithmetic and Cryptography
Students perform basic operations in modular (clock) arithmetic. Students encode and decode messages using shift and affine ciphers. Students apply their multiplication, division, addition, and subtraction skills.