The chapter describes a method of teaching practicals called iSPACES, which stands for innovation, Science, Practicals, Application, Conceptualization, Entrepreneurship, and Systems. This method of teaching represents interdisciplinary teaching that aims to motivate students to study science and produce useful products that fulfill the needs most students encounter in real-life situations. The discussion in this chapter is inspired by exploratory studies of practical work in science, technology, engineering, and mathematics (STEM) in Tanzania’s schools. The goal is to integrate practical work with what students learn in science classrooms, laboratories, and outside the classrooms. Examination of previous work and discoveries made by teachers of the iSPACES instructional method revealed the strategies for restructuring existing science curricula. Insights from this model enabled teachers to rethink the pedagogy of teaching physics, chemistry, and biology (PCB) to overcome students’ cognitive conflicts between their everyday world and the world of academic science. The chapter also highlights the contextual factors in the enactment of practical work in teacher training in Tanzania. The arguments underscore the challenges of integrating practicals in STEM science classes, a responsibility that ultimately depends on (1) the preparation of science teachers, (b) impetus to engage students in practicals, and (c) teachers’ mastery of science subjects.