Some teachers I have observed, particularly non-native speakers, have used the IPA most creatively in activities, and the learners have benefited.
Personal opinion only:
Whilst I have used IPA in most of the lessons in which I have had occasion to write on the board, I am wary about placing too much emphasis on 'teaching' it to students who use the Roman alphabet in their own language. I see my job as a teacher as enabling students to use the language (sorry about the platitude) for the purpose for which they need/wish to use it. I see no value at all in burdening learners with grammar rules, mastery of the IPA, labels for grammatical structures or parts of speech as ends in themselves, though acquaintance with some of these may help some students learn to use the language effectively.
I have asked learners to "listen to this recording, and underline the schwa sounds in the italicised words in this written version of the passage." I have devised activities for , for example /p/ - /b/ discrimination for English learners of Czech and Czech learners of English, for /l/ - /n/ - /r/ discrimination for Chinese learners of English, and for /y/ - /u/ discrimination for English learners of French. I have done this only to help the learners hear the different sounds and produce them accurately, not to help them learn the IPA symbols. I have never asked learners to transcribe words phonemically or to read phonemic transcription, though I have with trainee teachers.
When I have taught learners who have used either Arabic or Chinese script (my only two experiences of teaching learners whose written language does not use the Roman alphabet), I have taught them to read and use the English phonemic symbols. The benefits they appear to gain from this outweigh, for me, the disadvantages of an additional learning burden.
ps. I use different techniques depending on the learning styles of the learners I am working with. One thing is sure, however: every learner I have worked with since my return to ELT nearly fifteen years ago knows the word 'schwa' and the symbol /ə/