A foot is a little far even for a seedling. T5's can be out almost touching the plants. Even seedlings can be like an inch or two away.
How tall are your sprouts? I'm guessing they stretched for the light and now that the leaves are bigger, it's falling over. Like someone else said, they're top heavy.
To fix it now, tie it to a stake like a chopstick or a toothpick. To fix it later, when you transplant it, bury the stem deeper than you would normally.