The document discusses a study on using construction and demolition (C&D) waste as recycled aggregates in concrete. It describes a case study where C&D waste from demolishing Idlewild Elementary School was crushed and tested. Concrete mixtures using the recycled aggregates were developed. The study found that carefully separating C&D waste can produce consistent recycled aggregates. Concrete made with up to 100% recycled aggregates from the school performed acceptably. However, more research is needed and incentives may be required to increase market acceptance of recycled aggregate concrete.