Flanders, the northern, Dutch-speaking part of Belgium, is facing a growing intra- and interlingual diversity. On the intralingual level, tussentaal ('in-between-language') emerged as a cluster of intermediate varieties between the Flemish dialects and Standard Dutch, gradually becoming the colloquial language. At the same time, Flemish language-in-education policy strongly propagates Standard Dutch as the only acceptable language (variety) in the classroom, demonstrating the vigour of standard language ideology (SLI) in Flanders. This paper analyses the distinct ways in which teachers try to make sense of the gap between policy and practice, and how they act upon what is expected from them in a classroom context. By analysing interview data of eight teachers from a secondary school in the city of Ghent (East Flanders), I make an attempt at mapping their 'personal ideological frameworks', in order to uncover the ways in which teachers respond to language-in-education policies and strong standard language ideologies.