Sometimes, it is easiest to understand something new by understanding what it isn't, so here are some very general rules of thumb to consider as you work with students to develop project-based units:
If the main assessment for a skill is only a test, it likely isn't project-based.
If the main audience for a project is the teacher and classmates, it might not be project-based.
If the assessment or project involves only one way of knowing (subject area), it doesn't sound project-based.
If the project is completed by individuals in isolation, it may not be project-based.
If there is no connection to the real-world that the child experiences, it usually is not project-based.
Does that mean that skills are not ever taught in isolation? Almost. It means that any skill building is a mini-lesson leading to something greater that has a real-world focus and audience. An example: A teacher mentioned to me that he was thinking about having kids map out the actual dimensions of early-American homes, to see how big (small) they were. Great idea! So far, it is just an activity that needs to be pushed further to become project-based. Using that experience, the students could interview architects about modern home needs, could map out the dimensions of the colonial home in their own home to see how many rooms it would take, they could take the experience of less-is-more and inventory their closets, to see what wants/needs are represented and compare that to the wants/needs of colonial times. Last, they could do a photo-documentary of their findings and invite the home builders association in to view their own drawings of adequate modern home needs.
Every one of these ideas includes many, many other skills, which likely will need to be taught up front. While it may seem like this would take a lot of time, it will, but the relevance and deep, meaningful learning that will result is critical. PBL is not very linear, it is an organic approach that requires good planning, flexibility, and responsiveness to children's' interests and experiences.
