This research is distinctive in that parents' perceptions were utilised in conjunction with students' perceptions in investigating science classroom learning environments among Grade 4 and 5 students in South Florida. The What Is Happening In this Class? (WIHIC) questionnaire was modified for young students and their parents and administered to 520 students and 120 parents. Data analyses supported the WIHIC's factorial validity, internal consistency reliability and ability to differentiate between the perceptions of students in different classrooms. Both students and parents preferred a more positive classroom environment than the one perceived to be actually present, but effect sizes for actual-preferred differences were larger for parents than for students. Associations were found between some learning environment dimensions (especially task orientation) and student outcomes (especially attitudes). Qualitative methods suggested that students and parents were generally satisfied with the classroom environment, but that students would prefer more investigation while parents would prefer more teacher support. The study provides a pioneering look at how parents and students perceive the science learning environment and opens the way for further learning environment studies involving both parents and students.