Essential Questions for students (objectives): How can ratios help us convert monetary amounts?
Supplies: video (length 0:49), note-maker
CCSS: 6.RP.3d, 7.RP.3, Defend your answer
Time needed: 10 minutes
Instructional Format: Video, student problem-solving, group work
Vocabulary for a Word Wall: ratio, approximate, simplify
Lesson Description: There are many ways to use this video in your math class. I filmed it with the express purpose of stressing the importance of approximation and justifying your answer. There isn’t a “right” answer to this problem, which requires students to have to work hard to explain their choices.
1) You can show this video (0:49) at the beginning of a unit on ratios as a hook that will keep the students interested in learning about ratios. You can have them work on the problem at the end of daily lessons (or once a week) armed with new knowledge that they are exploring in class. Or you could revisit the video at the end of the unit as a formative check to see what the students have learned about ratios and whether they can apply that knowledge.
2) You could show this video as a warm-up activity after the students have learned how to convert between different measurement systems using ratios. It is a great way to show an unusual context to a ratio problem.
Extensions: What unusual monetary systems exist in the world today? Which one is the closet to the U.S. currency and which differs the most?