Pyret (and the Bootstrap curricula in particular, where we use both Scheme and Pyret [http://bootstrapworld.org/]) really strives to avoid the purely "bottom up" approach.

Curricula in Pyret focus on building games using concepts from math, or interactive simulations using concepts from physics, or data analyses using concepts from working with spreadsheets.

I agree that a purely "CS concepts"-based approach is dry and ineffective for a huge portion of students. That's why applications are so critical, and why we build things like tables (https://twitter.com/PyretLang/status/773605473824145408) into the language, so we can give students real-world tasks to do right away.

We happen to also have carefully designed the language to allow us to teach these applications along with a rigorous programming style. Students write _examples_ that get them ready to understand automated testing, they write _contracts_ that teach them about type-based interfaces, they write _data definitions_ that teach them about structured data, and so on. But it's always in service of an application.

So I very much agree that a purely "bottom up" CS-concepts-only approach has issues.