Explore the physics of soap films with the <i>SoapFilmScope</i>

Abstract This paper presents the SoapFilmScope , a versatile and inexpensive device designed for physics teaching at secondary school and undergraduate levels. Built from low-cost and easily accessible materials, the SoapFilmScope enables students to explore key physics concepts–wave dynamics, light interference, and fluid motion–through real-time observation of soap film behaviour under acoustic excitation. Using only a 3D printer, a smartphone, a loudspeaker, and basic components, learners can visualise capillary standing waves, interference patterns, and internal flow structures. The device is particularly suited for classroom demonstrations and student-led inquiry, offering both qualitative insights and entry points for simple quantitative analysis. Aligned with core physics curricula, the SoapFilmScope provides a hands-on platform for reinforcing fundamental topics in waves, optics, and fluid dynamics.