A graphic organizer, also known as knowledge map, concept map, story map, cognitive organizer, advance organizer, or concept diagram, is a communication tool that uses visual symbols to express knowledge, concepts, thoughts, or ideas, and the relationships between them.The main purpose of a graphic organizer is to provide a visual aid to facilitate learning and instruction.[Wikipedia]

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When introducing students to a new graphic organizer, you should describe its purpose, model its use, and provide students with opportunities for guided practice. Once students become comfortable with using the organizer, more independent applications are appropriate. In the end, you should encourage and assist students to create their own organizers.

Before Instruction

Teachers may use a graphic organizer to attempt to provide structure for the presentation of new material while indicating relations between ideas.
Teachers can elicit information from students by creating a graphic organizer on the blackboard to get an accurate idea of students’ prior knowledge

During Instruction

Graphic organizers can help students to actively isolate, process and reorganize key information. This is because graphic organizers allow students to approach subjects cognitively because they assist thinking.
The student must take an active role in learning while processing and reorganizing information. Modifying an organized structure of information gives students an opportunity to learn from their own mistakes. It also allows students to construct maps that are appropriate to their individual learning styles.

After Instruction

Students can construct their own organizers using the full text to isolate and organize key concepts. This summarization technique is a tool to see if students can interpret what was being taught and state it in concise, accurate terms.
Post-instruction graphic organizers also encourage elaboration. If a student can connect prior knowledge with what was learned and identify relationships between those ideas, they are actively learning.