I never learned how to...

[lippy]

I never learned proper formal dining etiquette.

[SuperUberBob]

Write with my feet.

[AvivaSimplex]

Drive a stick shift.

[cbloom]

[ QUOTE ]
I never learned how to tie my shoes the way that most people do ( http://www.fieggen.com/shoelace/standardknot.htm ). I mean, I know how to do it, but I've never used it enough to get really quick at it. I've always used the bunny ear method ( http://www.fieggen.com/shoelace/twoloopknot.htm ).

[/ QUOTE ]

ZOMG I just discovered I always tie a Granny knot !? From that site :

Do your shoelaces always come undone? Do your shoelace bows sit vertically instead of across the shoe? If so, you're probably tying a "Granny Knot", and one simple change to your technique will result in a balanced knot that sits straight and stays secure.

[furyshade]

do complex mathematical equations in my head

[IlliniLou]

[ QUOTE ]
Can't whistle or blow bubbles. People have tried to teach me. It just doesn't work.

[/ QUOTE ]
in addition: i dont know how to sneeze properly, i always hold my sneezes in,
never learned how to rollerblade or rollerskate or ice skate

[edfurlong]

Parallel park, I am but half a man.

[Blarg]

[ QUOTE ]
Ride a bike with no hands
whistle really loud with my fingers
throw a football in a decent spiral (that wasn't made by Nerf)

what part of childhood did you miss out on?

[/ QUOTE ]

All of those, plus:
surf(except body surf, which doesn't count)
do a back flip
do a good jumping spinning kick
do a cartwheel
stay on a boat for more than a minute or two without feeling sick and/or barfing
draw well
work on cars
do most anything "handy"
cook seafood well
ski or waterski

[illeagle]

Never figured out how to ollie on a skateboard. I tried alot too.

[soko]

Learn multiplication tables greater than 5. Don't you dare ask me what 7 times 8 is.