Math begins with one of Montessori's Great Lessons, The History of Numbers. Students begin their journey through mathematics by building the foundational concepts of quantities and numbers; quantities and values to 10, teens, 1-100, writing numbers, greater than/less than, odd/even, formation of numbers to the millions, sequencing, and order, ordinal positions, estimation, and rounding. Once the foundation is built, students begin to deconstruct numbers and quantities by using place value to represent whole numbers and decimals. This leads children into fraction concepts introduced to vocabulary, improper/mixed, nomenclature, representation. Students use all four operations (addition, subtraction, multiplication, and division) with fraction manipulative materials, decimal fractions, money, simplification of fractions, equivalencies, and Greatest Common Factor. An in-depth exploration of the Greatest Common Factor (GCF), Lowest Common Multiple (LCM), prime and composite numbers students begin to learn about multiples. Fractions are revisited throughout the elementary years with new concepts introduced, such as unlike denominators, mixed numbers using all four operations.