Diatoms are photosynthetic, eukaryotic unicellular microorganisms with distinctive cell wall structure made of composite organic material and hydrated silica, that inhabit all aquatic habitats. They are ecologically significant due to their ability to fix carbon, ability of primary production and due to them being excellent biological indicators of water quality status, so because of all that they are excellent model organisms in teaching of Nature and Biology. Diatoms are relatively poorly represented in the teaching of Nature and Biology, so it is important for students to become aware of the importance of this group of organisms, both in the context of ecosystem functioning and everyday human life. The aim of this paper is to develop teaching tools that will help teachers and students in using diatoms as model organisms and original reality. A collection of permanent microscopic specimens of diatoms to be lent to schools in 3 copies with 10 samples each was made, as well as models of cell structure of different types of diatoms and a draft of a future application that students will use in class when learning about diatoms. Learning outcomes from the National Curriculum for Nature and Biology were singled out and 10 separate topics suitable for teaching about diatoms were added. Ways of using diatoms in teaching as original reality and model organisms for the purpose of achieving separate learning outcomes were proposed, as well as a proposal for the preparation of a lesson in which diatoms are used as model organisms.