What were the "gifts" the kids were given and how were they used?

Calvin was given the gift of communicating with others, Meg the gift of her faults, and Charles Wallace the gift of his childhood. As a last gift, Mrs. Who gives Meg her spectacles and tells her to only use them as a last resort. They tell Charles Wallace that things will be especially dangerous for him, that they should never separate and that he should not think that he knows everything.