The basic building blocks of the whole numbers remain mysterious.

Life gets busy, and sometimes those basic math skills from school days get a little rusty. Whether you're budgeting, measuring for a DIY project, or just having a math-related brain teaser thrown your ...

Students in Melissa Williams' kindergarten class at the Westminster School in Atlanta, Georgia, practice connecting quantities to written numbers — a key part of number sense. Credit: Holly Korbey for ...