Scaffolding in Project-Based Learning

Project-based learning calls for students to work independently on high-level tasks.  The trick is this requires a variety of skills, including organization, reflection, self-assessment, communication, and collaboration to name just a few and most students, including the top ones, have a limited capacity with these skills.  If the instructor simply defines the final product and turns students loose to work on it, the result will most likely be a disaster.  As a result, a thoughtful teacher will provide scaffolding, giving students the support they need to reach the goals of the project.  Jamie McKenzie sets out eight characteristics of scaffolding, each of which I've tried to integrate into my PBL unit.

1. Scaffolding provides clear directions

Directions are the road maps that let students know exactly what is expected of them.  Since my project asks students to apply a version of the engineering design process, I plan to make that process explicit to students by sharing a diagram of the process with them as part of the entry event.  Throughout the project, the engineering design process can then be revisited to remind students of where they are at and where they are going.

For individual lessons within the unit, I've tried to vary the level of directions provided.  For some lessons, such as the Newton's 2nd Law Lab, I created detailed step-by-step directions that allow students to focus their attention on the analysis required and the potential application of what they are learning.  For other days, such as the days spent building or testing a product, I've identified what each group and each individual should have by the end of the class period, but have left it open how that product will be produced.

2. Scaffolding clarifies purpose

Students do best when they know the reason behind a task.  The entry event for the unit is an attempt to provide a real-world context for the project at the center of the unit.  Each activity is then designed to support students in completing the project.  In addition, each lesson has a learning target which will be presented to students to ensure they know what they should be getting from each lesson.

3. Scaffolding keeps students on task

People of all ages are naturally curious and can easily go off on a tangent when something is interesting.  In order to complete the project, students need a balance between room to explore and clear checkpoints to keep them from wandering too far off.  In my project, I've set a task for teams to complete each day.  By setting a clear objective for the day, students know what they should be working on, but have room for inquiry and creativity within the task.

4. Scaffolding offers assessment to clarify expectations

Assessments are not just for the instructor; a good assessment will also allow students to track their progress.  For two of the key products, an oral presentation and a team journal, I've created rubrics which will be used to assess the work.  These rubrics will be provided to students as they start these products to ensure they are aware of the criteria. 

5. Scaffolding points students to worthy sources

The Internet is an incredible repository of information, but not all of it is worthwhile or credible.  For students learning how to perform effective research, a few good resources provided by the instructor can serve as a starting point for the research.  Since my project includes minimal research in the traditional sense, this type of scaffolding still needs to be fleshed out in my project.  I plan to include a day for students to explore technologies currently used to reduce impact forces and to consider how these might be adapted to their own designs.  I can provide sources to students using a class website and Diigo, a social bookmarking tool.  One of the advantages of Diigo is students can add worthwhile sources they've found, providing their peers with a larger library of sources in the process.

6. Scaffolding reduces uncertainly, surprise, and disappointment

In order for a lesson to be effective, it should be tested as thoroughly as possible before students complete the lesson.  Even after this testing, lessons should continue to be revised and refined based on feedback and observations of the implementation.  This summer, I've been working on a version of this project as part of a professional development opportunity.  My writing partner and I have been testing many of the details of the engineering challenge used as a centerpiece of this unit in order to ensure all aspects work as predicted.  In August, we will be piloting portions of this unit with students in a STEM camp and using our observations to further refine the lessons and materials.  While I expect to further refine the unit each time I implement it in the classroom, significant testing of key lessons will inform even my first implementation.

7. Scaffolding delivers efficiency

Every action students take during a PBL unit should contribute to completing the project.  The use of the engineering design process as a framework for the unit will help students to focus on the path they are following to reach the ultimate goal.  In addition, the daily tasks assigned to students during the project will ensure that students know how to remain focused and efficient as they progress through the project.

8. Scaffolding creates momentum

As students progress through the project, their confidence and excitement for the material should build.  This form of scaffolding is less concrete than the others, but I have designed the unit to begin with relatively simple tasks which build to more complex.  Students will also move from presenting informally ideas to just a few peers to presenting to the entire class and a guest engineer able to provide real-world expertise in evaluating student products.  In other words, as students get closer to the end of the project, the stakes get higher.  At the same time, as students practice the skills which will be required at the end, they should find they are able to conquer the more complex tasks with confidence, in spite of a larger audience.