This paper demonstrates the efficiency of a marketing strategy, primarily digital channels, but also traditional. The main goal of the paper is to prove the following hypotheses: 1. Redesign of a Gaudeamus Gymnasium and GiGA Igraonica website lead to longer average session duration and easier finding of the required information compared to the status before redesign. 2. Strategic distribution of the same amount of budget to more marketing channels increases the number of responses to the content from a broader target groups compared to the more frequent coverage of a smaller number of channels. 3. Modified Content strategy for each target group achieves better results in digital advertising than the generic content, same for all target groups. 4. Involvement of an influencer reach more members of younger target audience and increases the number of their positive reactions to private education, compared to the reach metrics and positive reactions before influencer involvement. 5. Developed digital marketing strategy with included traditional media leads to greater number of conversions than unrelated advertising of digital and non-digital channels. Moreover, this paper deals with processes after determining that there is a need for the redesigning Gaudeamus Gymnasium's and GiGA Igraonica website. To be specific, bad analytics data and user experience revive the need for a new website. Furthermore, same steps are undertaken in order to maximize the potential of digital advertising channels. Marketing strategy was set in order to maximize the efficiency of advertising in 2018, which was susceptible to change according to the results and learning outcomes of previous campaigns. As a result of website adaptation and it's faster loading, the cost per click has decreased in digital advertising and by that increased the efficiency of the campaigns themselves. Macro Conversion for the High School and GiGA Igraonica is the enrollment of the new students. After a well-set and implemented marketing strategy, at the beginning of the 2018/2019 school year there is 61.54% increase od enrolled students in gymnasium and 27% more signed contracts for the GIGA Igraonica.