Our paper presents LIFT, a system that enables educators to create immersive virtual field trip experiences for their students. LIFT overcomes the challenges of enabling non-technical educators to create their own content and allows educators to act as guides during the immersive experience. The system combines live-streamed 360° video, 3D models, and live instruction to create collaborative virtual field trips. To evaluate LIFT, we developed a field trip with biology educators from the University of Central Florida(UCF) and showcased it at a science festival. Our results suggest that LIFT can help educators create immersive educational content while out in the field. However, our pilot observational study at the museum highlighted the need for further research to explore the instructional design of mixed immersive content created with LIFT. Overall, our work provides an application development framework for educators to create immersive, hands-on field trip experiences.