Effects of Aperture on Depth of Field
Practice using aperture by completing the Effects of Aperture on Depth of Field assignment found here
Hyperfocal Distance Photo Assignment
See the Effects of hyperfocal distance by completing the Hyperfocal Distance Photo Assignment here.
Click here for a click reference material on Aperture
Nikon Learn & Explore: Bokeh for Beginners
Understanding Aperture: Controlling Light Based on the Exposure Triangle
Hyperfocal Distance & Depth of Field Calculator at Photopills.com