IMO, the most prominent points that speak for Python as an entry-level language are these:
it has a shallow learning curve - going from nothing to "Hello world" is much faster than in most other languages
it is intuitive - the syntax was designed to follow the principle of least surprise, and it is very consistent overall (unfortunately, the standard libraries don't always follow this consistency)
it requires very little boilerplate: a typical "Hello world" is one line of code, and simple programs can be written without any additional background noise that needs to be explained (such as function declaration keywords, import statements, class constructs, preprocessor directives, etc.)
there are excellent, straightforward tools to work with python code, especially the interactive interpreter; you don't need to learn a build system, IDE, special text editor, or anything else to start using python - a command prompt, the interactive editor, and a simple text editor, are all you need
it uses dynamic typing, but unlike many other dynamically-typed languages, types are transparent, and type-related pitfalls are rare