It should be underpinned by allocated instruction time (see below). These can offer remedial or enrichment instructional activities. On average in the OECD, students in PISA 2012 reported spending 4.9 hours per week on homework or other study set by teachers, this was one hour less than reported on average in PISA 2003 (OECD, 2013b, Tables IV.3.27 and IV.3.48).