Does anyone have any advice as to how to speed up in these questions? These slow DS down, considerably!
I don't mean to sound sarky but I really think practice is the only way. Obviously he will do them in order of letters rather than each whole word, so all begin with t except one starts with a w, so reject that one, second letters all e except another word that second letter h, eject that one, and so on, letter by letter. Other than that just do loads of them. A game like Boggle might help him to get quicker at sorting letters in his head maybe......? And a bit more fun too!