Ultrasound imaging can provide visualization of the major part of the tongue, a difficult-to-see articulator involved in the production of most speech sounds. Within the past decade, there has been a growing body of evidence to support the application of ultrasound in the field of L2 research and pedagogy (Gick et al., 2008). Typically, the existing literature examines the effect of ultrasound training on improving the pronunciation of a difficult sound production by using a series of complex training sessions either individually or in small groups (Tsui, 2012). In the present study, we aim to explore whether it is feasible to use ultrasound visual feedback also in a classroom setting and to test its effectiveness in facilitating speech sound remediation when learners are only exposed to a series of short-time training interventions. The experiment was carried out over one semester at the English department of the University of Paris 3, using a Seemore PI USB-powered ultrasound system. The participants were seven French first year undergraduate students in English with a CEFR level of either B1 or B2. The relevant English sound productions were the contrasts between the two high front vowels /iː/ and /ɪ/, and the front open vowel /æ/ and the central open vowel /ʌ/. Both oppositions are known to be problematic for French learners (Flege, 1995) as the French vowel inventory has only one unrounded high front vowel /i/ and one open front/central vowel /a/. All participants were recorded at beginning (pre-test) and two weeks after the end of the semester (post-test) in a reading task which included 10 repetitions of the target words beat, bit, bat and butt in carrier sentences as well as one recording of the speech accent archive text Please call Stella. Each speaker also recorded 10 repetitions of French control sentences with comparative test items. Each participant received a ten minute ultrasound training session during regular language laboratory classes on a fortnightly basis, five sessions in total. The students worked in pairs and the training consisted of a discussion to incorporate explicit awareness of the tongue movements associated with the target sounds and repeated practice of the vowels, both in isolation and in CVC syllables. For two of the speakers, we carried out an additional pre- and post-recording in one of the session in order to evaluate the possible immediate impact of the ultrasound coaching on the pronunciation performance. All acoustic recordings were subsequently semi-automatically aligned using the WebMAUS system and the first three formants of the target sounds were extracted using PRAAT. We are going to present the results of the pre- and post-recordings for all speakers, focusing on speaker- and vowel-specific differences, and will discuss the various advantages, problems and pedagogical implications likely to be encountered when using visual articulatory ultrasound feedback in the classroom. References Flege, J.E. (1995). Second language speech learning: Theory, findings, and problems. In W. Strange, Speech perception and linguistic experience: Issues in cross-language research, pp. 233-277. Baltimore: York Press. Gick, B., Bernhardt, B.M., Bacsfalvi, P. & Wilson, I. (2008). In J. Hansen & M. Zampini (eds.) Phonology and Second Language Acquisition. Ch. 11, pp. 309-322. Amsterdam: John Benjamins. Tsui, H. M. (2012). Ultrasound speech training for Japanese adults learning English as a second language. Unpublished MSc thesis, University of British Columbia. Retrieved from enunciate.arts.ubc.ca/research-and-case-studies/other-research/.