Target group: studeNts For pupils, instead, the most difficult chemistry subjects in learning online were: ● Atoms ● Chemistry general ● Mixtures and pure substances Atoms was the most difficult topic for students to learn online, according to the teacher’s opinion, especially with regard toElectronic chains. Next, there is Mixtures and pure substances that gave the students problems with: -Methods for separating pure substances from mixtures (filtration, extraction, evaporation, distillation -Distinguish between pure substances and mixtures -Chemical elements composed of one type of atom At the same level we findChemistry general, which was difficult to understand in relation to the topic of Molecules PHYSICS TarGetGrouP: teachers For Physics, the most difficult topics in teaching online were: ● Density, pressure and buoyancy ● Forces ● Accelerated motion and Newton's second law The most difficult topic for the Slovenian physics teachers to teach online was Density, pressure and buoyancyin relation to: - Buoyancy - Density and specific gravity 12