Cantor
Cantor is a front-end to powerful mathematics and statistics packages.
8 Alternatives To Cantor
Beaker
Open Source Polyglot Data Science Tool
Calculist
The open-source, web-based thinking tool that facilitates effective thinking for solving problems.
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Carbide
A new kind of programming environment
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Eve
Programming designed for humans
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Kajero
Interactive JavaScript notebooks - create good-looking, responsive, interactive documents.
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Observable HQ
Interactive code examples/posts
iPython
iPython provides a rich toolkit to help you make the most out of using Python interactively.