By supporting children with disabilities, learning and support assistants have become an essential component of inclusive education in regular schools. Assistants in European countries have various levels of vocational training, but they do not consider themselves to be adequately qualified for what are often highly demanding duties. In an attempt to raise standards, five web-based knowledge boxes have been developed within the Erasmus+ project, 'Improving Assistance in Inclusive Educational Settings II'. The knowledge boxes are available open access through a learning platform and focus on different aspects of inclusion and disabilities. Learning and support assistants, as well as children from five different European countries, participated in the creation of this tool for professional development. In addition, the knowledge boxes are to be evaluated by assistants, parents, teachers and students in order to assess the impact of the knowledge boxes on the competencies in inclusive education of assistants.