This publication is the second of a series of seven supplementary investigative materials for use in secondary science classes providing up-to-date research-related investigations. This unit is structured for grade levels 7 through 9. It is concerned with food value of liquified cellulosic agricultural wastes: paper, straw, corn cobs, sawdust and food processing plant wastes. This guide provides students with the opportunity to study fungi (mushrooms) and the effect they have on common waste material found in and around the home and school. The first part of this guide describes: (1) materials needed; (2) preparing nutrient solutions; (3) sources for spawn; and (4) suggested reading. The second part provides students with background information and one laboratory investigation. The information consists of: (1) materials needed for a four-student team; (2) procedures; (3) questions for thought; (4) extending the investigation; and (5) suggested readings. (HM)