This activity was designed by Dan Meyer. It works really well in conjunction with Unit 2 of the CUNY HSE Math Curriculum Framework.
The goal of the activity is to give students a headache that has an aspirin in mathematics. In other words it’s about giving students a task that is a lot harder without the thing you want to teach them, in this case the coordinate grid. It takes about 5-10 minutes and it a great way to introduce/review/appreciate the coordinate grid.
It involves three images, linked above.
- Show the first and ask your students to pick a point and keep their eyes on it.
- Ask for two volunteers. Tell them you are going to have them try to describe where their dot is to the other person, only using words and without any hand gestures.
- Right before you have the first student try their description, go to the second slide, which takes the first image and adds more dots.
- Ask the first student to describe the location of their dot. Once they are done, ask the other student on a scale of 1-10, 10 being absolutely sure, how confident are they that they know where the dot is. If they are at an 8 or above, let them guess. If not, let the first student try different ways to describe the location.
- Once the second student correctly identifies the first student’s point, say, “Now it is your turn”.
- Before they start describing the location, go to the third slide, which lays down the coordinate grid over the image.
- Then have them tell the first student how to find their dot.
The point will be made without having to talk about it too much. You might ask students write about what they learned from the activity.
