First, students will learn how to convert larger units of time to smaller ones, in order to solve mathematical problems. Units of time will include seconds, minutes, and hours.

Converting units of time by Khan Academy

Convert to smaller units (sec, min, & hr) by Khan Academy

Next, students will learn how to convert larger units of time to smaller ones, in order to solve word problems. Just as before, units of time will include seconds, minutes, and hours.

Watch these Khan Academy videos, in order:

Conclude by giving your students these challenges:

Find the area of the green region:

Here's the solution: First, notice the center of the circle and the bottom right of the quadrant, are opposite corners of a square. Next, notice the quadrant is comprised of the square, plus 3/4 of the circle, plus twice the green region. The area of the square is \(2,\) the area of \(3/4\) of the circle is \((3/2)\pi,\) and the area of the quadrant is \(\pi(3/2 + \sqrt{2}).\) Removing the area of the \(3/4\) circle and the area of the square from the quadrant, we're left with twice the green area. Dividing this by \(2\) gives us the area of the green region, which is \((\pi\sqrt{2})/2 - 1.\)

In the figure below, the radius of the smallest circle is \(1.\) What is the radius of the largest circle?

Here's the solution.

Conclude by leading this investigation:

Siteswap (juggling number patterns)

by MathPickle