We have developed low-cost, miniaturized, lightweight, see-through, easy and safe to use desktop experiments with which engineering students can conduct investigations to learn fundamental principles of fluid mechanics and heat transfer. The ultra-low-cost of the experiments make it possible for engaging investigations to be integrated widely throughout fluid mechanics and heat transfer courses. With a target cost comparable to a textbook, these experiments make it possible for teams of students to pursue their own investigations of fluids and heat transfer phenomena.