Today we started by reviewing how to calculate the slope of a line given a graph. We talked about constructing rate triangles and counting the boxes on our graph to figure out the rise and the run.
Next, we looked at a problem where we had to calculate the equation of a line from a table of values.
These are both topics that we have visited many times, so the students were pretty quick to come up with their equation for each.
Next, we reviewed yesterday’s lesson on the interior angles of polygons.
I asked the students if they noticed anything or if could they make a connection that might help them figure out the interior angles of an n-gon (a polygon with any number of sides). To my delight, one of my students came up with this lovely example on their personal whiteboard.
Next, we moved on to the exterior angles of polygons.
We discussed how we could use supplementary angles to figure out the exterior angle if we knew the interior angle of the polygon. We worked on a couple together and students were noticing a pattern emerging involving 360 degrees.
We discussed the fact that the sum of the exterior angles for an n-gon is always 360 degrees. This would become very useful when making calculations for many-sided polygons.
Finally, we switched gears and went on to the scratch coding website. The new Ontario grade 9 MTH1W course now includes coding as part of the curriculum. I had the students play around on scratch and get to know the platform. Once we figured out how to get signed on to a free student account and insert a pen, we tried to create code to make a square.
That took us to the end of our class.
I hope something here was able to help you on your teaching journey.
Have a great day!