The purpose of the article is to highlight the possibilities of collaborative pedagogy, in particular mentoring, for the development of STEM competencies and soft skills of students and to present the experience of implementing the SchoolTechno programmes at Donetsk National Technical University. The implementation of the SchoolTechno project is based on the concept of STEM education and the principles of collaborative pedagogy, including mentoring, as effective tools for developing students’ professional competencies and soft skills. The direct beneficiaries of SchoolTechno are secondary school students who work in teams with their teachers under the mentorship of university students of technical and engineering specialties. The experts in the programme are university professors and representatives of business and the public sector. The participation of such a wide range of stakeholders is beneficial for each of the individual groups, as they share experiences and acquire completely new skills not specific to their target group while studying and working on projects. Moreover, the combination of STEM education, collaborative pedagogy, and mentorship in projects like SchoolTechno provides a fertile ground for the development of students’ creativity.