Heroes to meet
Look for counters, record keepers, merchants, and early number-system builders.
Open Math HeroesSubject Trail
Math Adventures by subject
Number Sense
Build an instinct for quantity, place value, comparison, estimation, and the patterns numbers make.
Terms to understand
Study digits, place value, number lines, magnitude, estimation, and rounding.
Open Math TermsProblems to practice
Use the related drills to strengthen this subject one problem at a time.
Open related practicePractice this subject