After years of being a single mom and relying on public transportation, we have mornings down to a science and are almost never late. The important part is the night before. Lunch for dd is made the night before. Back pack has everything it needs and is set by the door. Clothes, including socks and underwear are laid out in her room. My clothes are selected and my bag is ready as well.
We usually rise about an hour before we leave. I get up, take a shower, gently wake dd and put her clothes on her bed. I get her lunch out of the fridge and in to her backpack and make her breakfast. DD comes out of her room dressed, goes to the bathroom, brushes teeth, comes and eats breakfast. After breakfast, she'll watch a little of a DVD (we don't have any TV channels) but only after her shoes are on and her coat, hat, gloves, etc are lying on the couch next to her and she's gathered anything extra she wants to take to school (like chapstick). She knows that once we are walking out the door she cannot go back for anything.
WHile she's eating breakfast and/or watching the DVD, I get dressed and get myself put together. I give her a two minute head's up to get her coat on and we are out the door.
It took many years to get it all down, but I think having a really specific routine laid out works really well.
For a year or so we did have a problem with dd changing her mind about the clothes she had chose the night before. All of her school clothes are nice, soft comfy stuff, so she started wearing her clothes for the next day to bed. So she didn't have to deal with getting dressed or making any choices about what to wear in the morning.