Currently when a logged-in user enters khanacademy.org, you have to click through several menus to get back to where you left off. First it's "resume" on the specific module on the specific course, and then it actually gets pretty hard because from there you can only click on the squares for tests or scroll aaallll the way down and see what the last video with a checkmark is and then click on the next video.

If on the other hand you click on the square, that can only be a test. And since tests are often the last thing in a module, you often have to click next and then click on the video. That's 4 clicks from the home page to get to where you left off!

If there was just a big continue button as soon as you entered the site then sure, you lose specificity in where you're going, but it would eliminate a whole lot of resistance to learning :)