In most engineering courses, acoustics is only taught to a very limited extent. As a result, engineers often do not have sufficient knowledge when they have to solve problems in which acoustics plays a role. The Acoucou.org courseware platform aims to solve a part of this problem by offering freely accessible online courses that can be used for formal education and lifelong learning. The European project ASKnow, funded by the European Commission's Education and Culture Executive Agency, aims to offer five new, freely accessible online courses on the acoucou.org platform. The five courses are: fundamental acoustics, psychoacoustics, acoustic simulations and auralization, electroacoustics, and room and building acoustics. Each course consists of thirty lessons and two case studies. For each lesson, the theoretical part is complemented by an interactive part to promote the user's acquisition of the different concepts and by an assessment part to check the knowledge acquisition. The consortium, composed of academic and business institutions, is first introduced. Then the methods and tools for designing the courses are presented in detail. Finally, examples of implementation are presented. The difficulties associated with international cooperation in times of a pandemic are also discussed.