Welcome to the Bunnings Workshop community @SandiC1. It's fantastic to have you join us and many thanks for starting the discussion.
As we are an online community there are no physical classes that we run. You might like to check with your local store on the availability of such a class. However, you wouldn't be the first member that has joined us wanting to start doing mosaicing. We've managed to set them on the right track and they have now contributed some really great pieces of art.