I've had some (most) of the kids in my precalculus class for either 1 or 2 previous years, so they know each other. They've been in every seating arrangement possible, so they know each other. They're all friends, so they know each other. Therefore, yap yap yap yap. Sheesh were they chatty yesterday.
We've started ellipses, and I was having them create them yesterday with string and two pencils as "foci" and scratch paper. I started having them tie the string to the "foci" and work it that way, BUT a student showed me what she learned on Bill Nye the Science Guy (sp?) .... (love him). You make a loop with the string and put the foci inside and keep the string taut, and you get the same, neater result. Yay for learning new things.