Real Human Being
Join Date: Jul 2006
Location: Ottery St. Catchpole
Bikes: Sleeping Beauty: 2008 Jamis Aurora
Is there no other daycare place you can take your daughter?
It is probably a stupid question, but it seems like it'd be easier to find another place than to double your speed anytime in the near future. Plus you will probably have to deal with traffic, headwinds and flats at some time or other, so you'd need to be going way faster than 20mph for the rest of the commute. When I was commuting, it took me 10 minutes just to attach my bag, blinkies and headlight and remove/stow the u-lock.
I can't speak to the training part, but I do know of some other quick fixes to speed you up:
Get good gear and clothing, so you can move more efficiently with less discomfort (padded shorts, rain jacket) and not have to slow down because you can't see, for example (eyeglasses, headlight/taillights)
If you have knobby tires, replace them with flat-resistant slicks/road tires
Ride the fastest bike you can afford
Don't carry anything that isn't vitally important
I used to give myself an extra half-hour just in case I had a flat, so the idea of getting the whole commute done in a half-hour sort of blows my mind a little.