Essential questions start students off on a journey and help them develop related questions that organize and direct their search for knowledge. Project-based, constructivist learning emphasizes problem solving using the idea of an essential question as a starting point to set the stage for further questioning.
Essential questions are important because they provide a teacher with a thoughtful approach to a course or to individual units. They help the teacher understand the usefulness, the relevance, and the greater benefit of a particular topic in a course or unit. Essential questions are usually thought-provoking to students and can be used to stimulate discussion, debate, dissent, and research.
Take a real-world topic and begin an in-depth investigation. Base your question on an authentic situation or topic. What is happening in your classroom? In your community? Select a question about an issue students will believe that, by answering, they are having an impact on. Make it relevant for them. The question should be a “now” question — a question that has meaning in your students’ lives.
Read: The Question is the Answer – http://questioning.org/module/module1.html