No one claims it鈥檚 an easy way to teach, but proponents of project-based learning say it is far ahead of other approaches in motivating students and helping them thoroughly learn more of what counts.
But critics and advocates alike warn that enthusiasm for PBL can go too far鈥攑roducing parodies of effective projects, failing to play to individual teachers鈥� strengths, and wasting precious class time.
Ben Daley, the chief academic officer of the High Tech High charter school network based in San Diego, is deeply committed to PBL. Still, he lets his new teachers start slow. 鈥淚 tell them to just do what they know to do really well at first,鈥� he said. 鈥淚f they go crazy with a big ambitious project and [do] not accomplish much, what good is that?鈥�
Return to the main story,
Israeli experts friendly to project-based learning suggested on a recent visit to a High Tech High campus that the schools might have become too good at squeezing out classroom talk by teachers. Lecture-style instruction, they argued, can include narratives that stick with students just as well as hands-on experience.
Daniel T. Willingham, a cognitive psychologist at the University of Virginia, in Charlottesville, said the criticism points up a common misunderstanding of constructivism, the well-established theory that learners make knowledge and are not just recipients of it.
鈥淥ne of the big mistakes people make when they think about constructivism and trying to apply it to the classroom is the idea that learning has to be active, by which is meant physically active,鈥� he said. Rather, it鈥檚 mental activity that counts.
E.D. Hirsch Jr., who has written often on the importance of an explicit, well-crafted curriculum, said care is needed to ensure projects are not sidetracked by faith that children will learn good stuff as long as they鈥檙e engaged in doing.
鈥淭here鈥檚 no substitute for watching plants grow,鈥� if you are learning about plants, he said. But, he argued, too many activities turn out to be tangential.
Mr. Hirsch and others say, too, that PBL can present huge 鈥渙pportunity costs鈥� in the classroom, because other methods can induce understanding in less time. For disadvantaged students, who have fewer opportunities to learn academic content outside of school, that鈥檚 a particular problem, according to Mr. Hirsch.
Mr. Willingham said cognitive science so far does not give PBL the decisive edge over other teaching methods that some of its advocates say that it has. Teacher talk and demonstration, cooperative learning, and case studies鈥攁ll might be effective and, indeed, all could play a role in project-based learning, he said.
鈥淚 don鈥檛 think any method is obviously superior to any other,鈥� he said. 鈥淚鈥檇 take any method done well over any method done in a mediocre way.鈥�
