The idea of supplementary education is based on the assumption that high academic achievement is closely associated with exposure to family and community-based activities and learning experiences that occur both in and out of school in support of academic learning. Supplementary Education may be described as the common-sense stuff that well-informed adults spontaneously do to entertain, to occupy and often to add to and support the formal learning experiences of learners. In everyday life these may take the form of music lessons, camping, bedtime stories, reading together, shopping, chores, museum trips, travel, or almost any of the experiences that broaden and enrich the awareness, skill level, or knowledge base of learning persons.

Supplementary education is consistent with many notions drawn from concepts associated with cognitive science. These include:

• the connection between, amount of time and one’s exposure to learning
• selective attention
• the richness of the pool of prior knowledge
• redundancy in the experience base
• the socialization of learning experience
• collaboration and learning
• accommodation of multiple perspectives
• learning and the sense of trust that is born of human interactions

 Supplementary education expands and enriches the mental capacities of the learning person while at the same time it renders those capacities more adaptive. It can be argued that in reality it is school or institutional learning that is supplemental to the fundamental learning that occurs in the course of living, yet we have come to think of formal schooling as providing the primary education source and these other alternative or additional sources as supplementary to them. 

Edmund W. Gordon