Hi Yolanda,
How about
Calvert �s Descriptive Phonetics: Introduction and Transcription Workbook
I think Roberto Merino has also published a good handbook
But you need something for your students to write down the symbols after listening... Mmmm... Some websites will give you online phonetic transcription but they won �t "read it out" for you...
http://upodn.com/phon.php
https://easypronunciation.com/en/english-phonetic-transcription-converter#phonetic_transcription
http://www.photransedit.com/online/text2phonetics.aspx
...or if they have an audio tool it �s after the transcription, not before
https://tophonetics.com/
So... Not sure that helped, I �ll keep searching
Regards