Sam turned around and saw a girl - Slytherin, judging on the manner of greeting, or perhaps a Ravenclaw - approaching him, presumably she was the one who had "You" which he had almost felt sure was aimed at him.
With a quick shrug and a look which read "I don't really care," he nodded, budging over a little and making room for her to do her part in the preparations. "I didn't realise this was a partnered exercise," he said in reply, but again he shrugged, and this time gave a nod, moving to gain a better view of the cauldron.
While it may have seemed like the easy way out, watching water (In potions) was actually a rather delicate exercise. If it's not boiled then you've just wasted those ingredients you've tossed in, and will have to start again, however if it's gone too hot, then you wont know that that "Shrinking solution," you've made, is actually a wart growing potion until you drop a teaspoon full into your mouth, or even worse, onto your toes - there was nothing worse than an itch in a spot like the foot that you just couldn't scratch.
"What year are you in?" he asked the girl as he faced away from here, working to set up a separate cauldron, this one for the "Half-sister" potion, so that they wouldn't have to make one potion, then sit around waiting for ages for the second one to boil.
"Which one are we making first?" He asked, this time bending his neck around to see the girl.