We have been fortunate to be associated with 20 wood energy projects located in school facilities throughout the western United States, beginning with the first “Fuels for Schools” project in Darby, Montana in 2003.  Beyond the savings each district has been able to divert to educational purposes, Fuels For schools projects were conceived with project based learning in mind.

Essential questions that can be presented to students of all ages include:

• Where does our energy come from?
• What is the heat value of wood?
• Will our air quality improve if wood is burned in a wood-fired boiler rather than an open slash pile or forest fire?
• What is the impact of thinning forests on wildlife habitat and water quality?
• Where does the waste from the combustion process go to?
• What is the impact of using wood to heat a school on the annual school budget?
• What is the impact on local economy?

The Fuels For Schools program required each school to develop curriculum materials in support of the project.  I have observed learners gathering samples of wood fuel in order to determine the moisture content of a recent load of fuel.  The actual analysis is fairly straight forward—bake the moisture out of a sample with a microwave in order to determine the moisture content—but the results determine how much a school pays for their wood fuel, determine critical adjustments to the wood-fired heating system and illustrate the concept of diminishing returns.  For example, if a five pound sample of wood is baked for ten minutes and loses 2 pounds of moisture and is then baked for another 10 minutes and loses only ½ a pound of moisture, how long will the learner need to bake the sample before they can be confident that the majority of the moisture has been removed?  A more advanced learner might be asked to determine how much energy will be needed to dry the wood, and how much energy will be derived from the remaining wood.

The forest health questions provide opportunities to study recently thinned forest land and to document how thinning activities impact wildlife, water quality and the fire resistance of the remaining vegetation.  A typical thinning process removes approximately 10 tons an acre in wood fuel.  Learners can explore how many acres would be thinned to heat their school for a year (typically 75-150 acres), and where those acres are located in their community.  A long-term project can be developed to study how many years will pass before the forest has produced an equivalent quantity of material.  The cycle in dry western forests is between 10 and 20 years and may be as short as 1-5 years in warmer climates.  Because the volume of woody biomass is related to climate, fire cycles and other factors, learners become engaged in an international conversation about energy and forest health.

The waste products and emissions provide another opportunity for learners to compare the use of wood to the fossil fuels they displace.  Many communities don’t think twice about the emissions from their fuel oil burning equipment and the particulate, sulfur and carbon they produced.  Using wood as a heat source presents opportunities to explore the carbon cycle and to understand why the vegetation of today is not capable of absorbing carbon produced millions of years ago.  Schools have experimented with a wide variety of wood fuels and have produced potassium-rich ash piles suitable for fertilizing gardens and lawns and well as craggy piles of clinkers that seem to be more suitable for creating artificial coral reefs or jewelry.  Learners can analyze the waste products and determine the economic costs and benefits associated with ash and clinkers.

The Fuels For Schools program http://www.fuelsforschools.info/ has built a network of schools, teachers and learners to continue to explore these questions over time.  Each school has integrated the curricular requirements in different ways, but all have opened the door to minds that are curious about the world around them and the impact of choices we make each day.