The popularity of the educational robot in K-12 classroom has dramatically increased in the past decades to engage students studying not only Science, Technology, Engineering and Mathematics (STEM), but also 21st-century skills. Most educational robots tend to be as simple as possible such that the lower grades can benefit from the robotics technologies safely. However, such design consideration makes most educational robots with none or minimal sensing capabilities. However, it is very important for senior students to learn more advanced robotics concepts and applications. This paper presents a concept of extending educational robots’ sensing capabilities through quipping an external microcontroller. The paper also demonstrates how the framework can be easily used in sensor-based applications through a line-following example.