Under the conditions of the COVID-19 pandemic and a full-scale war in Ukraine, the lack of computer equipment for conducting online chemical experiments is experienced. In connection with the implementation of the New Ukrainian School and the development of STEM education, there was an urgent need to develop domestic educational computer equipment. The Department of Physics and Chemistry of H.S. Skivoroda’s Kharkiv National Pedagogical University is developing the SchoolKit software-methodological complex (PMK), which is based on three universal software tools: ColorKit, ChemKit, SoundCardScientificKit. When creating applications, only free software is used, which ensures low cost and, accordingly, accessibility for a wide range of users. A computer polarimeter was developed based on the ColorKit software. A new principle of polarimeter operation is proposed, which is based on computer processing of the image that occurs when optically polarized light is passed sequentially through an optically active solution, a transparent plate with internal tension, and an analyzer. A high-speed computer polarimeter based on a CMOS matrix was developed, a working model was manufactured and tested. The device differs from others since it uses a fundamentally new way of processing visual data and does not contain any mechanical components and polarization modulators. It is also easy to manufacture, and quite reliable. The polarimeter software allows data to be accumulated in the form of tables and displayed in real-time graphical form. The computer polarimeter was used for two years during laboratory classes in the “Mechanisms of Organic Reactions” subject, including online mode. In particular, it was used to experimentally determine the constants of acid hydrolysis of sucrose at different temperatures, concentrations of acid and sucrose. Visual display of measurement results, stability of device operation and good reproducibility of experimentally obtained data allow intensification and/or optimisation of the education process due to the automation of polarimetric measurements. After some improvements and validation, the device is planned to be used in scientific research.