I still say Racket is the best because it was designed from the ground up to teach great programming skills. Realm of Racket and How to Design Programs are best in class in my opinion.
I haven't used racket, but I would still lean towards languages that are heavily used commercially. The IDE support is generally better and the online resources are plentiful.
When you use the popular your average skills are lower. Also teaches you bad habits. Learning programming is different than learning a language. Once you learn programming you just learn syntax to learn other languages.
Also, Python might be popular but it is almost always the second-best option for whatever task you're doing. I still like to use the best tool for whatever I am doing.