Upper Elementary, 9 to 12 years The Montessori principles of self-directed, individualized learning are fully expressed in the curriculum of the upper elementary classroom. The child at this developmental stage of life shows a growing capacity for tackling real world problems. They demonstrate a sense of collaboration, social conscience, values, and morals. The students can harness their imagination into spoken and written form. Their reasoning ability is profound and they enjoy turning concrete experiences into abstract thoughts, words, and mathematical/scientific formulas. The Upper Elementary curriculum is rich in concrete experiences and materials in which students explore their developing consciousness and abilities. It also contains daily interdisciplinary lessons which integrate history, geography, mathematics, science, manuscript, language arts, geometry, literature, research, art, practical life skills, and music.