This is Pamela, from the Khan Academy computing team, and creator of the curriculum. It's loosely based on our CC-licensed materials from GirlDevelopIt SF, which I started developing while I was at Google and that we've been teaching for the last 4 years. Those materials are at: http://www.teaching-materials.org/htmlcss-1day/
If you have feedback on any of the challenges, please click Report-a-problem, I'll be improving the automated graders tomorrow. If you have other feedback, leave it here or email us at compsci-feedback@khanacademy.org
Ah, the <_> is meant to imply that you have to figure out the tag name to put in there, the _ is a placeholder. What would make that more clear?
(We do colored boxes in our JS hints, but I was going to avoid that complexity until necessary in HTML. It's possible it's already necessary).
I skipped to this activity and didn't read the instructions, so I didn't see the part about line breaks. It seems to me that a good solution would to be have the green guy mention the line break, or some other reinforcement of the fact that the goal is a line break.
If you have feedback on any of the challenges, please click Report-a-problem, I'll be improving the automated graders tomorrow. If you have other feedback, leave it here or email us at compsci-feedback@khanacademy.org