This publication is the sixth 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 10 through 12. It is concerned with the crystallization of an enzyme, lysozyme, from egg white. The first part of this guide provides the teacher with: (1) materials needed; (2) suggestions to facilitate classroom use for the investigation; and (3) suggested readings. The second part provides students with background information and one major investigation - crystallization of lysozyme. The investigation 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)