The article shows the didactic opportunities o f experimenting and modeling to organize physical thinking. As exemplified in the construction o f the sign models o f the activity o f external electrostatic field onto the moving sandgrains of sand clock, scientific understanding of observing effects is shown.

Keywords: thinking, experimenting, modeling, model, learning activities, method of scientific cognition.

The article reveals the nature and methodical danger o f methodological mistakes in teaching physics. The author addresses to the specific issues o f the teaching practice: definitions in teaching physics, models usage in physics, the problem o f description, physical tasks w ith methodological content.

Keywords: methodological mistakes, teaching activity, motivation, methodology, scientific method o f cognition.