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Math Tourist: Stalagmites Take Forever

**Essential Questions for students (objectives):** How can you use multiplication and standard measurements to solve problems?

**Supplies:** video (length -0.39), note-maker

**CCSS:** 4.OA.2, 4.NBT.5, 4.MD.1,2 TEKS: 4.8B, 4.8C, 4.4H Math Modeling

**Instructional Format:** Video, student problem-solving, group or individual work

**Time needed:** 20 minutes +

**Lesson Description:** There are many ways to use this video in your math class. I filmed it with the express purpose of modeling a standard measurement conversion problem that relates multiplication and place value. The information also touches on cubic inches which can spark a rich discussion on 3-D modeling.

1) You can show this video (0:39) at the beginning of a unit on converting within standard measurement as a hook that will keep the students interested in learning about conversions. 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. Students use the note-maker to help record their problem-solving work. Or you could revisit the video at the end of the unit as a formative check to see what the students have learned about conversions within a measurement system and whether they can apply that knowledge combined with multiplication and place value.

2) You could show this video as a warm-up activity after the students have learned some basic conversions. It is a great way to show context to conversions that isn’t the same old conversion worksheets.

**Extensions:** What did the Earth look like the year the stalagmite started to grow? This would be a wonderful connection to science and social studies!