Installation directory for WordPress and child theme

Actually, there is no “correct” directory structure. One of the great strengths of WordPress is how many options exist for configuration. Tricks like using a local config file, for example, allow you to work in so many different ways.

That being said, what you have outlined is a very standard file structure and should suit you just fine.

If you do not want the /wp/ portion of your file system in your site URL, take a look at Giving WordPress its own directory