In April 2013 the Hewlett-funded OER Research Hub (OERRH) Project, in collaboration with the Flipped Learning Network (FLN), conducted an online survey of flipped educators with the aim of finding out about their use of open educational resources (OER). This paper presents the results of this survey in relation to what school teachers consider to be the impact of OER on students in a flipped classroom; two brief case studies are introduced to exemplify how OER use leads to increased student engagement in their learning process.