The vision for the EU-Citizen.Science platform is to aid in the mainstreaming of citizen science, bybuilding a sustainable platform as a learning space for citizen science in Europe for researchers,citizen science practitioners, policy makers, journalists, citizen scientists and other stakeholdergroups. To achieve this aim, the project supports the development of ~20 training modules on awide variety of CS-related subjects, aimed at this range of stakeholder groups. This Deliverablepresents 24 training modules, 17 of which are from various Consortium partners and not thepromised 3 but 10 modules developed by Cascading Grants awardees, drawing on the expertisefrom 10 institutions or individuals outside the Consortium. We describe the Moodle platform andthe structure and topics of these training modules, the training and evaluation processes used increating them, and the protocol created for future users of the eu-citizen.science platform who maychoose to create their own training modules during the years 2022-2027. We also report how webuilt on our earlier work identifying specific training gaps in the field of CS, using a survey and aworkshop to select the topics of the modules and widening the scope of topics and availablelanguages with the call for Cascading Grants. Finally, this Deliverable concludes with somerecommendations for maintaining the sustainability of this platform, highlights potential topics forfurther training modules to be written in the future and provides some recommendations based onlessons learned for other CS Projects who may wish to provide CS training in the future.