One of my favorite programming tutorials is "Write Yourself A Scheme." It's not "Here's the language, here's the API, etc" it's "Let's accomplish this task. Here's some documentation. Here's a breakdown of what you need to do. Figure out how to do it." There's no answer key to the exercises, either your solution worked or you need to redo it.

https://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_...