Kathleen's mum. I just taught DD9 fractions exactly like this. I showed her a simple fractions addition and asked her how to do it. She wanted to add top and bottom rows. So I told her to stop and SEE 1/2 and SEE 1/4 and to then look at it again and she was good to go after that, did a whole sheet of additions and subtractions of varying difficulties. It makes sense to me that your DD would have no trouble doubling measures in a recipe but might not translate that some time later to written fractions on a page.
