Learners of primary and secondary schools in Slovenia have many opportunities to compare their knowledge and skills, obtained at different school subjects, with peers, while participating in competitions, organized for these subjects. Some competitions already have respectful tradition of few decades and among these physics competitions can be included.
Competitions are organized for two basic reasons. The first one is to promote and popularize particular school subject among wide as possible population of learners. The second one - not less important - is to detect those pupils, who have strong interests and also potentials for the highest achievements in particular disciplines. If we want to get to those more capable and interested pupils we have to offer them appropriate challenge and opportunity to test themselves and also to compare to others. Trying to accomplish both goals (to promote and detect the most promising) is necessary a frustrating activity. A balance should be achieved between the number of reasonably simple tasks, which can be successfully solved by a solid majority of participants, and more difficult, new, challenging problems to address and activate the gifted pupils. If all the problems are easy we can easily miss and also lose the gifted and if problems are too difficult we will lose inclination of majority.
We will present how a reasonable balance between these two contradictory goals is obtained in physics competitions for pupils in primary school. We believe the present form of the three-level physics competition facilitates popularization of the discipline among the learners at the school level, providing that certain number of more complex tasks are given already on this level. They are a selection tool, which allows to filter out the best, who enter the next, more demanding, challenging, exciting and rewarding levels of competition.