This curriculum guide for the Plano Intermediate School District (Texas) Outdoor Learning Center is divided into three major sections. Section I provides information on the numbered stations/posts found along the perimeter and inner trails of the center and includes brief comments on the philosophy of environmental education and the history (geology, land use) and use of the trails (trail construction, signs, general rules). Section II is designed to provide background information for teachers using the center and includes a sample permission form; guidelines for student preparation (permission form importance, safety, conservation/preservation, general rules); emergency procedures; list of common/scientific names, locations, and characteristics of plants found at the center; common/scientific names, habitats, and other information on animals found at the center; and geological information. Section III provides a list of seven goals for K-12 environmental education and an extensive number of science unit plans. Each unit plan includes title; key concepts; content area; grade level; objectives; classroom, campus, site, and/or supplementary activities with related instructional strategies; and instructional resources. A bibliography, feedback form, and list of features found seasonally or at varied locations on the trails are also provided. (JN)