Snape looked up at those bright green eyes, as ever looking quite odd in a scanty boy's face. Standing, he strode over to the cauldrons, meaning to see what sort of trick or deception Potter had decided to pull this time. His gaze got darker the farther he got into inspecting the cauldrons. His first pass, he simply checked to see if the boy had forgotten one or two. On his second pass, however, Snape merely wanted to find some mistake, no matter how insignificant, - to send the boy back to work.
Students never finished the cauldrons. That, as ever, wasn't the point of detention. Snape had, through long years of study attained a system of categorization. Your average spoiled pureblood girl would be lucky to finish one cauldron in three hours, whereas her male counterpart might bestir himself to do as many as three. A halfblood, no doubt unused to house elves, would probably make it through about a third of the cauldrons. A Muggleborn? Used to dishes, many of them would do well to pull off half the cauldrons, and call it a night.
Potter had finished the entire lot, in an hour. Snape thought quickly, a dark scowl tarring his face. He couldn't... wouldn't... keep Potter with absolutely nothing to do. And the boy was too young to be trusted to chop ingredients.
Snape idly noted that Potter hadn't so much as moved an inch, while Snape had conducted his inspection - nor afterwards, when even the best child was prone to fidgeting (undoubtedly finding something that they could have improved). Snape looked down his long nose at the boy and said, "You are dismissed. You may make up the rest of your detention on Wednesday and Sunday. Do not shirk your homework, as my detentions take precedence." Yes, Snape thought, this will do quite nicely. Three times the work, for a single detention, and less wasting of my time to boot. Besides, half the Hufflepuffs could be counted on to scotch the Shrinking Solution - thus ensuring a supply of nearly ruined cauldrons for said detention.
"Yes, sir." Potter said in a perfect politeness that young Draco hadn't managed despite years of teaching. Snape chalked Potter up as yet another bully that needed an audience to really get going - Lupin had been like that, all nicety polite except when his friends surrounded him, and then just as vicious as the rest of them. No matter, Snape was not going to suffer another Potter's cheek. Not as long as he stood as Potions Master and Professor. He had a duty to the school as a whole, in fact.
[a/n: Snape's quite good at self-justification. You've noticed?
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