Not exactly. For discovery learning with advanced learners, this is true and small groups are more approriate.
With the corpus-based approach to language pedagogy, the traditional 'three P's' (Presentation C Practice C Production) approach to teaching may not be entirely suitable. Instead, the more exploratory approach of 'three I's' (Illustration C Interaction C Induction) may be more appropriate, where ‘illustration’ means looking at real data, ‘interaction’ means discussing and sharing opinions and observations, and ‘induction’ means making one’s own rule for a particular feature, which ‘will be refined and honed as more and more data is encountered’ (see Carter and McCarthy 1995: 155). This progressive induction approach is what Murison-Bowie (1996: 191) and Aston (1997) would call the interlanguage approach: partial and incomplete generalizations are drawn from limited data as a stage on the way towards a fully satisfactory rule.
There are some exercises designed for use in classroom with Xaira and the BNC Baby:
http://www.oucs.ox.ac.uk/rts/xaira/exercises/
For lower levels of learners in large classes, the teacher can still use corpus data by preparing the corpus materials carefully beforehand (e.g. edited KWIC concordances for blank filling). The horizontal and vertical contexts are very helpful for students to identify patterns and learn how to use language in context.
I am aware that corpora are not very popular with linguists, and particularly language teachers in China - corpora are mainly of interest to compuing specialists - becuase most of them do not know the corpus methodlogy themselves. I believe this is what this site is for - promoting corpus research and use in China.