This morning we observed the tadpoles and they didn't look much different - the back legs were perhaps a bit "meatier" but that was it.
After supper tonight I went to check on them and a couple of them now have their front arm(s)!! The kids and I are excited. I believe at this point they stop eating and will absorb their tail for food. As far as we can see (they move quickly and hide amongst the rocks and shells) one tadpole has both front legs and one tadpole has one front leg.
We added a thick stick to the tank and one of the tadpoles crawled onto it - fun.