In this paper, we report on survey and focus group data relating to the activities and perceptions of learning with Web 2.0 technologies of students aged between 11 and 16 years in 27 UK secondary schools. The study confirms that these learners had high levels of access to Web 2.0 technologies and that Web 2.0 activities were prolific. However, patterns of use were complex. The types of activity evidenced by the study suggest that learners can be categorised into four main groups: (1) "researchers": mainly in terms of reading with little evidence of critical enquiry or analytical awareness; (2) "collaborators": mainly with respect to file sharing, gaming and communicating; (3) "producers" and (4) "publishers": mainly in terms of sharing experience through social networking sites. Whilst most expressed an interest in using online technologies to support familiar school activities, such as presentations or for communication, learners seemed cautious about other values associated with Web 2.0 tools, such as the shared construction of knowledge in a public format. Few learners were familiar with the complete spectrum of Web 2.0 activities and only a small number were engaging in more sophisticated activities, such as producing and publishing self-created content for wider consumption. There was little evidence of groundbreaking activities and only a few embryonic signs of criticality, self-management or metacognitive reflection. The paper concludes that these higher order thinking skills need to be encouraged and supported in any attempt to use Web 2.0 for learning in formal education. (Contains 1 figure, 2 tables and 1 note.)