Glad you are enjoying them Manda! :-) You can just do a quick one here and there to keep your brain alert and put all that info you are learning from the short term to your long term memory as you engage with the terminology in different ways.
"The urinary system, including the kidneys and the bladder, is essential for maintaining the body's good health. Test your knowledge with our quiz for a healthy urinary system."
Check out this blog posting with the key info about the metric system.
Follow the links (in brown) that show you how to convert... and move the decimal places... a series of neat little flash animations!