This article is from the Recreational Figure Skating FAQ, by Karen Bryden with numerous contributions by others.
Every parent has had the experience with buying shoes or other
clothing for a growing child and having them no longer fit after only
a few weeks -- and not due to shrinkage, but due to a growth spurt.
Unfortunately, feet grow erratically, and the growth is not always
accompanied by an increase in height.
If you buy children's skates too loose, they will interfere with the
skating and may actually be dangerous because of lack of support. They
may also repeatedly raise blisters. If you buy them too small, or have
your skater continue to skate in them for some time after they have
become too small, either the skater will quit (because it hurts so
much), or the skating will suffer, OR the feet will suffer -- perhaps
To check the fit of the skates your child has now, ask him to put his
skates on loose and put his foot right to the front of the boot. If
you can put an index finger between his heel and the back of the boot,
he has enough room to grow. When he skates, check to see if his skates
are perfectly upright.
The only way to lessen the impact of keeping children's feet in skates
that fit is to buy used skates (on consignment, or at skate swaps),
and to sell your outgrown skates as well. Used children's skates are
very available and usually in far better shape than used adult skates.
Get the children's coach to help you select them, (and yours, too, if
you go that route) so that you don't get stung.
You can buy gender neutral brown boots if you plan to have the skates
passed on from girl to boy etc.