It worked. Using a slower ISO and a slower shutter speed I was able to get okay shots of the kid in the tub. I'm beginning to understand why our teacher, when repeatedly asked what sort of setting you'd want for <insert situation here>, he'd simply say "it depends". Because you can use a variety of settings to get similar results. So, what I hope happens with time and practice is that I begin to understand which methods to use for the given situation I'm in. Something tells me I have a very long way to go.