Hi Jamin:

There are a variety of recycled drywall/gypsum products that will qualify for LEED MR Credit 4 (recycled content).

EcoRock is made using 80% post-industrial recycled waste, including waste from steel and cement plants and uses no gypsum. As it contains no gypsum, EcoRock may be safely disposed of in landfills if necessary. According to Serious Materials, the manufacturer of EcoRock and QuietRock, the products have been used in over 35,000 projects.

Depending on where you are located, a San Francisco company called CleanBoard, which produces 99% recycled-core gypsum-based drywall products which may qualify for up to eight (8) LEED points. The company uses carbon offset credits to produce a zero carbon footprint in the manufacture of its products.

If you specifically require "impact resistant" drywall, Georgia Pacific offers DensArmor Plus® High-Performance and Abuse-Resistant non-paper-faced fiberglass mat interior panels. In addition to qualifying for LEED credits under MR, IEQ and ID, the GP products are the first and only gypsum drywall products to receive GREENGUARD and GREENGUARD Children & Schools(sm) Indoor Air Quality Certifications. GREENGUARD certifications recognize indoor products that have low emissions of volatile organic compounds (VOCs).

As the manufacture of building materials results in approximately 12% of the U.S. emissions from coal fired plants, to the extent that a company is able to reduce it's contribution to greenhouse gas ("GHG") production, while also incorporating recycled content, will help towards as many points as possible.

Good luck!
Green-Buildings.com