“…In science education, multimedia offerings with elaborate interactivity and feedback loops are used in formal settings to prompt reflective thinking with the intention of guiding learners' understandings to those more congruent with current scientific understandings (see, e.g., Coller and Scott 2009;Crook, Sharma, and Wilson 2015;Stieff 2005;Wieman, Adams, and Perkins 2008). Contrary to the expectation that such interactive multimedia would dominate formal learning, linear videos in the form of lecture recordings (Yeung, Raju, and Sharma 2016), video slices with classroom-based learning cycles (Mayo, Sharma, and Muller 2009) and social media sites sharing short videos are providing fierce competition and 2 Citation: Research in Learning Technology 2019, 27: 2280 -http://dx.doi.org/10.25304/rlt.v27.2280 (page number not for citation purpose) gaining popularity (Rosenthal 2017;Tan and Pearce 2011). Whilst YouTube channels such as 'CrashCourse' and 'Khan Academy' support formal learning through their links with curricula (Gray, Lindstrøm, and Vestli 2017), it is not unusual to find teachers using carefully selected videos from other channels such as Smar-terEveryDay and Veritasium in their classrooms (CrookedScience 2019, pers.…”