Current instructional emulation platforms often present limitations, either by overly simplifying operating systems or by offering hardware emulation that is too complex for students to fully grasp. This results in a gap between academic learning and real-world applications in both operating systems and computer architecture courses. EDUsim is introduced as a solution to these challenges, offering a modern, extensible emulation platform built with C++ that bridges the gap between hardware and software instruction. As a highly portable and modular operating system, EDUsim allows students to interact with realistic yet comprehensible system components. The platform enables a range of use cases, from fully emulated environments to interactions with real hardware, making it suitable for both OS and architecture instruction. The abstraction layers in EDUsim, including CPU and device models, enable rapid hardware emulation while maintaining flexibility. This paper discusses the design and implementation of EDUsim and explores its potential for improving instructional approaches in computer science education.