When we started, Barry was regularly confusing b and d, and his mother and the school were worried about this, as it is often seen as a sign of "dyslexia". Observation showed that this error tended only to happen at the start of a word, and not when the letter appeared in the middle or the end. My approach, when he made a mistake, was to move to another word with a b or d at the beginning, teach that, and return to the word that had caused the problem. I didn't tell Barry he'd got it wrong, but, again borrowing the idea from Sue Buckley's work with Down syndrome, simply indicated that he needed to think again. I didn't put b and d words together and ask him to discriminate between them, but praised him every time he got one right, and worked in the way just described when he made a mistake.
Barry couldn't make this week's lesson as he had a bad cold. However, his mother remarked when she phoned me that his school had noticed an improvement in reading words beginning with b and d. This progress is, I think, consistent with the evidence below on worked examples.