In defense of the author, I believe this is intended for experienced developers who want to stay sharp on their coding skills. With that said, even beginners need to start somewhere, and a couple of these projects are decent starting points. In reality though, you would not code these types of challenges in vanilla javascript, you would most likely use them to increase your skills in a preferred framework, such as Angular or React. Part of being a good developer is learning how to problem solve, which means investigating the functionality and figuring out how to implement it.