after i wake up i generally don't feel like writing about my dreams. I just remind myself periodically of what happened in the dream throughout the day and i remember them. then after school i come home and write them. Is that a bad thing to do? i have a fairly good memory when i want to remember things.

i think that if you fell that you are remembering the dream sufficiently then i'm sure you're fine. Pay attention to smaller details though, not just the big picture.

I prefer to use a dictation machine, which I
talk into after each Dream. My dreams are then
played back later in the day, and I finally
type them up into my dream journal which is an
excellent program called Neurobin.

I think you should write them down as soon as you can so that small details aren't forgotten. Like if you can't do it before you leave for school in the morning, try writing it down before class starts, or some other free time.

but.. if you think your recall is good enough that you can write them down in the afternoon... go ahead! ^_^

You really have to write your dreams down immediately, or large parts will be erased. You probably already know this; you wake up, remember a dream, you think you'll remember it later on but by the time you write it down somehow large parts have gone missing. Somewhere in our brains is an erase button. As yet we don't know why or how it happens, bus our dreams are almost completely erased from out memories unless we take action. In order to enable your brain to store more dream memories, you have to remember as much as you can, so writing it down immediately is the best way.
By the way, I hate this part. It's cold outside the blankets, I'm sleepy, my dream seems uninteresting, etc. But it's the best way to improve dream recall and come closer to LD's, so I do it anyway.If you really want to LD you should too.
Having said that, if you fail at this it is still better to write them down later on than not at all.
Ok, pleasant dreams and lotsa discipline