A considerable number of primary schools in Australia and overseas organise their students into achievement-based classes for literacy (and/or numeracy): a practice often seen in high school settings. Why school systems do this will be examined elsewhere, though it is safe to say that concern for ongoing student achievement is a consideration. Whilst much of the early research on achievement grouping focussed on academic outcomes, with a general consensus that there are no overall advantages for students, more recent overseas studies have investigated affective outcomes for students. No relevant research in the Australian primary context has been identified. This paper examines the attitudes of participating teachers towards this practice, as evidenced through interviews with eight teachers across three schools. It discusses how teacher beliefs related to the strategy impact on their classroom practice in literacy lessons. The conclusion reached is that teaching practices are negatively impacted by the regrouping strategy, and that this is ultimately detrimental to student learning.