We have some Giant African Land snails born about 3 weeks ago, and they don't seem to have any shells! I know when they're born their shells are almost see through but they don't seems to have shells. Does this mean that there is something wrong with them?
Have you added some extra calcium to their diet? That cuttlefish bone the petshops sell for birds is ideal. Just put it in the corner of the tank soft side up and they will soon be all over it. Not absolutely sure if the young will now grow a shell though, but I would say yes.
The shells are transparent when first hatched, but they soon grow. They will feed on the egg shells if left in the tank, but do need cuttlefish for calcium to help their shell growth. Tip for moving them: let them climb on a lettuce leaf. Enjoy.