Yes, Carld hit it on the head - floating skimmer.
Personally, I wouldn't even do that, since a non-swimmer can drown in a 2" puddle, making the pool a foot or two lower doesn't eliminate ANY of the danger, it adds to the danger since you will no longer be able to count heads, and your post will be to stand permanently at the edge of the pool, actually, having it higher will keep the kids aware of the danger and not give them a false sense of security that the lower level would.
My son learned in our pool, for the first while he was a stair hugger while he watched everyone else, then one day, while I was swimming, he asked if he could try to swim across (30 foot pool), I said sure, so he took off the lifejacket and swam across AND back without so much as a gasp. He still has that respect though since he cannot touch bottom yet.