The professional activities that constitute the work of school teachers are known to be both numerous and varied. While managing teacher workloads is a major priority for governments around the world, valid and reliable figures are difficult to obtain. From a larger qualitative study of teachers' work culture in Singapore, we report data obtained from six teachers through work-shadowing methods. The latter we argue overcomes weaknesses in existing research using pre-determined survey categories. Our results showed that the professional work of these teachers were as varied (although variable across the year) as their counterparts elsewhere and that the total time spent on work activities ranged from 45 to 65 h per week. While this upper limit seemed slightly higher than that from other locations in the developed world such as the UK, the findings based on our sample do not support the claim that teachers in Singapore--a highly achieving system--devote considerably more time than school teachers elsewhere.