\input zb-basic \input zb-matheduc \iteman{ZMATH 2013b.00343} \itemau{Thompson, Ian} \itemti{To chunk or not to chunk?} \itemso{Math. Teach., No. 227, 45-48 (2012).} \itemab Summary: Ofsted was asked to provide evidence of effective practice in the teaching of early arithmetic, its report entitled; ``Good practice in primary mathematics: evidence from 20 successful schools", was published in November 2011. Did this report pass you by? Unfortunately, as with many other reports not blessed with a ``high profile" the findings have little impact on those teaching primary mathematics day-by-day. The Ofsted evidence is reviewed here with some insightful comment and opinion. The policy makers are supposedly signed up to ``evidence based practice", well, put quite simply, here it is. (ERIC) \itemrv{~} \itemcc{D32 F32} \itemut{teaching methods; elementary school mathematics; instructional effectiveness; problem solving; computation; mathematical logic; arithmetic; difficulties; algorithms} \itemli{http://www.atm.org.uk/journal/archive/mt227.html} \end