If you have previously recommended this thread, you should see a tick / check mark on the recommend button. Click the tick to undo the recommendation (the tick may appear to change to a cross as you do this.) If you added a comment with your recommendation, you will need to delete that from your facebook wall separately.
Thanks Dixiebell. I'd seen the water babies website but didn't really want to travel all the way to Bordon. I hadn't seen the Tadpole Tots one - they have classes in Hindhead so will definitely give that a go. Thanks so much for the info.