Hall, Gaston, Molière: Tartuffe (Southampton: The Camelot Press, 1977), pp. 51-62 (section 3: Style) - this is a really good example of how to analyse alexandrines in terms of verse, comedy and social/historical context.
Hutier, Jean-Benoît, Tartuffe (1669) Molière (Paris: Hatier, 1993) - this is ordered thematically but the study of characters (or religion etc.) relies upon references from the text which could be useful for both the essays and commentaries
Molière, Le Tartuffe, ed. by Richard Parish (Bristol: Bristol Classical press, 2004) - Introduction and the notes at the back - the notes (pp. 88-110) are not a commentary but they are easier to understand than those of the Pléiade edition and whilst they contain far more information than a commentary needs, they might be useful to show the students how each line has lots of meanings and how the verses themselves relate to specific themes - i.e. reason, comic devices etc.
Edward James and Gillian Jondorf, Racine: Phèdre (E book: Cambridge University Press, 1994): http://0-ebooks.cambridge.org.pugwash.lib.warwick.ac.uk/ebook.jsf?bid=CBO9781139166423
*Kathleen M Hall, Rabelais: Pantagruel and Gargantua, Critical Guides to French Texts 88 (London: Grant and Cutler, 1991)
*Françoise Charpentier, Gargantua de François Rabelais (Paris : Pédagogie moderne, 1980)
*Dorothy Gabe Coleman, Rabelais: a Critical Study in Prose Fiction (Cambridge: CUP, 1971)
This web page, which is a BAC guide, offers a simple outline for a close reading of the chapter on education: http://www.bacdefrancais.net/gargantua-rabelais-23.php