Juan,
Thank you for asking. This is a great question to explore further. Does anyone else want to help Juan out? I hope others will chime in.
To me, the core of our theory is that a well-designed project creates a challenge or “need to know” that motivates student learning of both knowledge and skills.
If pressed further, I would say the tasks required to complete the project are “authentic” in that they mimic, more or less, work in the disciplines or across disciplines. An effective project cannot be completed without learning and applying new knowledge and skills. Students have to apply what they know and adapt it, responding to (appropriately scaffolded) twists or challenges that they have not previously seen or understood.
Planning and conducting effective PBL is hard work, but many teachers find it is worth it (especially when they are given appropriate support and opportunities to learn this approach). Once there is a strong “need to know” in your class it becomes easier to teach (and for students to learn) essential knowledge and skills. Because students are motivated they will seek out information and pay more attention to lessons/materials/tasks, and be more supportive of each other. The experience may also be more memorable and conducive to different learning styles.
Some aspects of PBL that can be motivating include a strong “driving question”, an enticing entry event, presenting to peers and other audience members, the chance use creativity in coming up with solutions, the chance (more helpful for some students than others) to incorporate their own initiative or values, to move around and get their hands dirty, work together, etc.
My feeling is that this theory applies to any subject area, even though what is being learned may be different.
Is that what you were asking, or are you looking for a more academic discussion of theories and references?
(e.g., http://www.bie.org/research/study/powerful_learning)
Do you have different ideas or questions about how or why PBL works?
Jason
