This study investigated the perceptions of science and math educators and their students at the Lebanese University related to online teaching and learning during the Covid-19 lockdown. For this purpose, two questionnaires were elaborated and validated based on two theoretical frameworks: The Community of inquiry for online learning environments and the Online collaborative learning theory. 35 educators (14 math and 21 science) and 245 students (109 math and 136 science) participated. Results showed that both science and math educators, with no significant difference between them, adjusted their courses for online teaching utilizing new resources shared with students. Online teaching allowed them to create an interactive community that encouraged students to explore concepts, construct explanations, apply and reflect on their learning. Both science and math students agreed that online learning enabled them to be more independent to explore new ideas and reflect on them with the instructor playing the role of a tutor rather than a knowledge transformer. The findings imply that online environment can allow active learning, and can provide the opportunity for students to acquire skills like, problem solving, critical thinking and collaboration. Further research is recommended related to critical thinking in online environment.