In accelerated algebra I, we are working on rational functions, so I thought I would open with Dan Meyer's 3 Act on The Leaky Faucet.
Act 1: We watched the video of the ducky in a bathroom sink with a leaking faucet. I asked them what the question might be. One student asked the all important question - WHY is the faucet leaking? We decided to answer - How long will it take to fill the sink? I asked them to write down a guess. They were working in groups of four on big whiteboards.
Act 2: They are getting really good at these and know what information they need to ask for. They asked for the "area" of the sink, which we were able to determine as a class she meant to ask for the volume of the sink. They asked for the rate, so I gave it to them and they got to work. They quickly discovered they needed to actually write down their units to keep it all straight. I allowed them to use the internet to figure out how many milliliters are in a gallon. Four out of five groups got it but I didn't tell them. I showed them with Act 3.
Act 3: Reveal the time-lapse of the sink filling up. They were excited at first, but then, wait, oh, is that hours, oh, we must be wrong. Then, they noticed, no, maybe we were right. Ahhhhh, yes, we were right!
Wrap up: I asked one volunteer to explain her process to the whole class to help the group that didn't get it. They were getting hung up on the drops which they really didn't need.
Have you tried any 3-Acts yet?