Monthly Archives: July 2021

Indirect Measurement #mtbos #made4math Monday!


In reading Building Thinking Classrooms and considering how to defront my classroom, I’ve found I need to purge lots of stuff! Getting ready for year 27, well, that means I’ve got a lot of stuff!

Several shoe boxes, most labeled correctly with what they contain, but a few are in disarray. I have run across many items from early years of having little to no money to spend, but I have always said, these are the times you are most resourceful and creative.

Homemade Hypsometer

I always said Geomtey was a favorite to teach because there are so many hands on tasks you can implement. I feel like this task likely came from a lesson in Discovering Geometry, Michael Serra.

I remember using one with a protractor attached in later lessons. And also having a mirror students placed on the ground to sight the top of their object to measure, and then shadows… we would use multiple approaches to measure then compare our results.

Even way back when it was obvious to me to allow students a time to reflect. Which tool was easiest, most challenging to use? Within their groups, they would discuss which meathod(s) seemed most accurate.

I always remember during these tasks students struggling with setting up their proportions. Reasong if their answer made sense within the context. It was a great opportunity to allow them to figure out corresponding parts as they would sketch the scenario on their recording sheets.

I loved these measurement tasks, then later using the protractor to make connections back to our previous indirect measurement tools. It gave them prior knowledge to have a foundation as we began a new way to measure with angles.