Make examples more concrete

[raacampbell]

Make it more interesting by making the examples more concrete. e.g. for the variable stuff at the start we could do things like:

weeks = 52;
daysInWeek = 7;
daysInYear = daysInWeek * weeks;

For the plotting of the lines, we could have them overlay two different Google trends. We tell them that two trends are plotted, give them the trend search terms, but not which line is which. Have them deduce which is which based on the data.

Think of something for the image data and histogram.