The purpose of this research, firstly, aimed to develop integrated environmental education activities for solid waste management in Libong Island, Thailand. The activities were built on an integrative research approach which consisted of four elements: inquiry process, participatory process, Participatory Rural Appraisal (PRA) and Appreciation-Influence-Control (AIC). Secondly, the research aimed to compare achievement of knowledge, attitude, awareness, skill and participation in solid waste management between an experimental group (32 participants) and the control group (32 participants). Participants were selected using voluntary non-random and purposive methods from village representatives, students, teachers, religious leaders, government and local community authorities. The research used the Pretest - Posttest Control Group Design. The research tools were an instructional plan of activities and achievement tests. Data were described in percentages, with normally distributed data described by mean and standard deviation. A t-test was also used to test the research hypothesis. The research results found that the integrated environmental education activities consisted of four learning units and 13 activities. In addition, participants in the experimental group performed significantly better in achievement tests on knowledge, attitude, awareness, skill and participation at 0.05 level. This indicated that the activities succeeded in imparting knowledge, increasing skill and participation as well as creating a positive attitude and raising awareness in solid waste management. The finding can be applied to developing best practices in solid waste management for other municipalities under similar circumstances
