Many Montessori materials are used throughout multiple age groups, first giving children a foundation at a young age and then becoming more complex as they are prepared to complete more complicated work.
Pegboard
The pegboard has several uses both in Lower and Upper Elementary. It can be used for finding multiples of numbers and least common multiples in fractions, but the favorite use in Upper Elementary is for the squaring of numbers, and later, for the extraction of the square root of a number. The patterns seen with the pegs are reminiscent of the patterns found in the binomial and trinomial cubes which were used sensorially in the primary environment.
Trinomial Cube
Use of the trinomial cube builds upon work done sensorially in the primary environment, where he or she internalized the pattern of the rectangular prisms that make up the cube. Each prism or group of prisms represents a term in the trinomial equation. The children in the upper elementary classroom come to understand, even derive, the algebraic equations just as mathematicians do: in finding the relationships between the prisms/components which make up the cube. Later, they use the cube to extract the cube roots of numbers.
Sentence Analysis
Students in both lower and upper elementary environments utilize sentence analysis materials in order to diagram sentences. This allows the child to understand the functions of parts of speech and sentence elements in a sentence. Understanding the elements of a sentence helps them to become better writers, and ultimately, more effective communicators.