When used in education, the word "schema" refers to the system of prior knowledge a student brings to the study of a given subject or topic. Because the brain learns best and most efficiently when making associations and connections between new information and knowledge already processed and understood, teachers can help their students learn by providing opportunities for the students to relate new ideas or techniques to knowledge they have already mastered. Schema theory presents a formal explanation of this process.
Before introducing a reading lesson focusing on use of context to decode unknown words, the teacher may present a sentence ending in an unknown word and offer a variety of suggestions regarding what the word might be. Students can use schema already in place to determine that the word doesn't have the letters to make the sounds of some of the suggested words, is too short to be some of the lengthy suggestions, doesn't make grammatical sense based on their experience with spoken language, wouldn't fit the illustration provided with the sentence. These are all approaches with which the students may already be familiar, making them part of the schema to which new methods of attack for decoding unknown words may be attached.
When an elementary science lesson is being planned to introduce the concept of matter changing from one form to another under given circumstances, the teacher might ask students to explain what happens to an ice cube left on a counter for three days. Based on their previous experiences, the students will realize that the ice melts into water and some will go further to understand that the water evaporates. This is drawing on the students' schema of past experiences and awarenesses to prepare them for learning new terminology and concepts such as solid - liquid - gas.
Prior to introducing the figuring of sales taxes in a secondary math class, the teacher may have students describe experiences of shopping for items that cost more than the amount listed on the sales tag. By comparing different items, the students will become aware of the pattern that the amount of additional cost increases in proportion to the cost of the original item. Bringing out the students' prior experiences with sales taxes activates the schema of awareness about the topic in preparation for the addition of new concepts or procedures for figuring the amount of such taxes.