Projector screens and electronic files are often used to communicate information in the classroom. However, issues with these methods include variable visibility depending on seating location and effort to create operation manuals. With a desktop screen distribution system, the operation screen is distributed to the student’s PC, thereby mitigating these issues. Furthermore, an Audience Response System (ARS), as a bi-directional classroom tool, increases student motivation to participate in classroom activities. We have developed NetScr, a teaching support tool that combines the functionalities of screen distribution and ARS. This study investigates the effectiveness and usefulness of NetScr based on data obtained from classroom practice and students’ evaluations.