Barbara,
I have several baby gates in my house to prevent my little trouble makers
from destroying the place.  I've run into two problems with them: the wooden
gates have gaps they can climb through, and one of them is too short.
 
Fortunately, I've fixed both problems at once by stapling heavy-duty plastic
sheeting on the gate.  By extending the plastic higher than the top of the
gate, the fuzzy can't grab the top of the gate with their claws.  Also, I
extended the plastic past the end of the gate so they can't squeeze past the
gate against the door frame (that part had to be reinforced with a chunk of
cardboard).
 
This should also let you climb over the gate, since the plastic is somewhat
flexible.
 
Jimbo, Mia and Pace
 
PS.  I'm still one step ahead of these little monsters, but it's probably
just a matter of time.
[Posted in FML issue 1465]