A brief look behind the flat 2015 to 2019 TIMSS

It is noteworthy that mathematics roughly stalled between 2015 to 2019, in both South Africa and Morrocco, despite the fact that both countries have displayed rapid improvements in the past – here the reference is to the Morocco trends seen in the graph, and in the case of South Africa trends seen since 2002 in three different international programmes3. [...] The distributions of results in the two countries for 2015 and 2019 in mathematics are illustrated in the next graph. [...] In Figure 4 the improvement in Morocco is clear, though there were more outliers – this is also reflected in a slightly lower correlation across the two years in Morocco of 0.96, compared to 0.98 in South Africa. [...] The item ‘MN11158’, a clear anomaly in the South African data, is not included in the Morocco graph as this item appears not to have been administered in 2019 in that country. [...] The pattern points to improvements at the very top and bottom ends of the socio-economic distribution, but a deterioration in the middle.