As stated in an answer to a different question I had, Activating a wand (or stave) does count as casting a spell.
A good cleric (or a neutral cleric of a good deity) can channel stored spell energy into healing spells that she did not prepare ahead of time. The cleric can “lose” any prepared spell that is not an orison or domain spell in order to cast any cure spell of the same spell level or lower (a cure spell is any spell with “cure” in its name).
So this comes down to channeling stored spell energy, which I think is an apt description of a scroll (or even scrolls and potions, just with different activation methods), and the lose of the prepared spell.
So could a good cleric have a wand of Air bubble (1st level spell CL1) into a spell of Cure light wounds CL1?