This cross-sectional descriptive study assessed general environmental health literacy among students focusing on their knowledge, skills, attitudes and behaviors regarding the environmental health, stewardship, and sustainability, using a questionnaire consisting of 35 core questions from the Centers for Diseases Control (CDCs). Students (N = 185) from three high schools in the district were asked through their class teachers to voluntarily complete the questionnaire. Results indicated that about 41% (n = 77) of the students lacked knowledge regarding potential sources of radiation exposure and 70% (n = 133) lacked knowledge regarding radon gas being the number one risk factor for lung cancer among non-smokers. Additionally, the ANOVA test indicated significant knowledge differences among school location. Students in school #1, located in the most affluent area, had significantly higher knowledge scores (M = 4.39) than school #2 located in a moderately affluent area (M = 3.50). Furthermore, we found significant differences in ethnicity on the environmental health attitude of the high school students. Black students reported lower positive environmental health attitude (M = 29.86) than White students (M = 32.63), Hispanic students (M = 32.33) and Asian students (M = 33.84). These findings demonstrated knowledge deficiency in some key areas in environmental health particularly the environmental diseases and conditions caused by manmade hazards such as pesticides, chemicals, radiation, air, water, and soil pollution. Targeted educational interventions to increase awareness and understanding of health effects, exposure to environmental hazards and carcinogens as well as risks associated to direct exposure as in this study, radon and radiation, should be provided to high school students. Practical education through tours where students can observe directly and participating in laboratory experiments could empower the students to translate this knowledge into positive environmental health behaviors and practices now and in the future.