Water pollution has been one of the major issues of the present time. It is essential to educate students regarding this issue and its possible solutions. In this article, a demonstration of a typical adsorption-based water cleaning process is presented. The removal of methylene blue (MB) and detergent from an aqueous solution is demonstrated using rice husk as the adsorbent. Quantification of the MB removal was achieved with the help of a smartphone-based colorimetry process. This demonstration would be helpful to students for understanding the adsorption process, calibration curves, and waste management. The kinetic study of adsorption will help students learn various kinetic models and their applications.