This activity was created by Dan Meyer.

Tell students they are going to watch a brief video (50 seconds). Let them know you’ll play it at least twice. Play the video for Nana’s Paint – bit.ly/Nanaspaint twice.

Nana’s Paint Mixup from Dan Meyer on Vimeo.

• After the second viewing, ask if anyone needs to see it again. If not, ask for a volunteer or two to explain what happened. If students don’t mention the number of spoonfuls of red and white paint, ask if anyone remembers. It’s likely that students won’t remember the exact numbers. If that’s the case, simply play the video one more time, asking students to attend to the numbers. Even if 1-2 students do remember, it is worth watching the video again so all your students can see.
• Give out the handout, Is It Too Late? Allow students to start with a couple of minutes of independent think time before having them work in pairs or small groups. 
• NB: The second URL offers some push and support cards to help dial up and dial down the problem for students. To learn more about using push & support cards, read Push and Support Cards: A Bridge to Advanced Math for a Mixed Level Adult Education Class
• Have students share their strategies and reasoning.
• Watch the reveal video (24 seconds) – https://bit.ly/Nanaspaint-Answer