Reality technologies are being introduced in schools due to high anticipated or claimed educational benefits. This article explores the reliability of foundations of such claims for use of three kinds of technology-based 'environments': virtual, augmented and mixed reality. It is a follow-up of a previous stage in a research review and includes 35 articles. A variety of problematic issues appear, among which can be found 'false dichotomies,' 'lack of precision' and 'neuromyths.' Examples are also given of fruitful approaches.