In the first of the seven books, siblings Jane, Katharine, Mark and Martha find a magic
wishing coin in the 1920s. But as wishes wont to be in stories, the wishes don’t work out
as planned. This particular magic coin is only half-magic, granting only half of every wish
(including time travel wishes), and leaving the children with the amusing challenge of
finishing up the other half of the wish on their own. Sometimes it works out when they
wish for twice what they want. Other times, not so much.
Don’t you see? She wished she were home and ended up halfway home! I wished there’d
be a fire and got a little fire! A child’s-size fire! Martha wished Carrie could talk
and she can half talk!