I tried at activity a couple of weeks ago which I’d often heard about, but never done before – a minimal pairs telephone. The previous week, I’d set my groups a writing task and whilst I was marking them, I noticed recurring issues with this and these when used as demonstratives. It’s a common problem for Spanish speakers because of the length of the two vowel phonemes – Spanish has a short /I/ sound, but not a longer /i:/. This leads them to make mistakes when writing, especially if they don’t proofread their work before handing it in!
So, after looking at the written task and highlighting the errors with this/these, I projected the table below and told them I was going to tell them my telephone number.
I then quickly read my telephone number as words, then again more slowly in sets of three. It was amusing, as they struggled to hear the difference as well. After pair-checking and confirming the answer, I drilled the words and encouraged them to stretch their mouths for the longer /i:/ sound. Then they read their telephone numbers to each other.