Although not unheard of, there is a scarcity of intermediate-level concepts (not as generalizable as theories, but with an applicability wider than a single technology or intervention) in technology-enhanced learning (TEL) research. In this paper we propose ‘strong TEL concepts’, as intermediate-level bodies of design knowledge that are both grounded in research evidence from multiple technologies and contexts, and have clear theoretical connections. We describe the main features of this kind of concepts, along with a practical method for developing them as valuable research contributions. We also propose ‘purposeful disengagement’ as an example of strong TEL concept, to ignite the dialogue in our community about the necessity and benefits of this kind of knowledge to support both TEL design and theory advancement.@en