This article is from the Recreational Figure Skating FAQ, by Karen Bryden with numerous contributions by others.
1. Look at how thick the dull strip is on the sides of the blades
along the edges. They were three or four millimeters when new. If
they're now thin, then your blade has been sharpened many times. The
concern here is that the rocker may be distorted after many
sharpenings, and it is almost impossible to restore without
2. Put the skate upright on a table, and check the position of the
bottom toepick. The blade should also be touching the table within one
or two inches of the toe pick. If the blade touches the table further
back, it means that the toe-pick is too low (probably a consequence of
successive sharpenings). If the blades touches closer than 1 inch, the
master toe-pick may have been ground off. In this case, the blades
will be useless for learning spins and jumps.
3. Ask the skate sharpener at your rink to examine the blade. They can
tell you if the blade is bent, incorrectly mounted or obviously
damaged by abuse or bad sharpening.
If the only problem is that the toe pick is too low, ask your shop to
grind it some to raise it. Never have the bottom (master) tooth ground
off your blades unless you only intend to use them for figures.
Otherwise the tooth fairy will never forgive you!!