We focus on the difficulties that visually impaired students have when dealing with graphics and diagrams in their study of geometrical optics. This case study suggests practices that use low cost materials, easy to find and to handle, and that provide a tactile perception for visually impaired students. The activities employ light and easy to carry magnetic boards and different types of magnets, mainly shaped rubber magnet strips. A student-centered learning method, namely Karplus's learning circles, is adopted.