Frame analysis - clash of frames

S1: can I use the stapler, Monsieur?
T1: parle français!
S2: it's not nine o'clock yet, Monsieur
In this exchange, code choice marks a clash in frame perception, particularly whether the boundaries of the present situation are to be understood in spatial or temporal terms. Whereas from the teacher's perspective, speaking French characterises the larger setting of this particular school (he invokes spatial brackets), from the student's point of view code choice counts as a marker of 'official  classroom activity' (he invokes temporal brackets). Interestingly, the student's persistence in using English (S2) underlines his refusal (note that the same refusal could have been voiced as ce n'est pas encore 9 heurs).
Data recorded in an elementary school, 8th grade, Ontario, Canada
Example quoted from a paper read by Monica Heller at the Conference on Political Linguistics, December 1995