This trainer's guide is intended to assist supervisors of work-based career training projects in helping students compare the advantages and disadvantages of buying or building a greenhouse, make a decision within cost constraints, and execute the task under supervision. This project is designed to meet the needs of trainees who are of low academic ability. The guide is one in a series of core curriculum modules that is intended for use in combination on- and off-the-job programs to familiarize youth with the skills, knowledge, and attitudes necessary for success in the workplace. Included in the guide are the following components: project information, a summary of the content and approach of the guide, supervisor's notes, background information, lists of tasks and core skills, an action plan that includes suggested learning activities, supervisor and trainee review sheets, and an assessment form. (KC)