Chocolatey is a package manager for Windows similar to Linux's apt-get, based on Microsoft's Nuget tool and Powershell scripting language. It works from the command-line and from a WPF GUI interface.
Chocolatey still has a large moderation backlog - however you can install unmoderated versions by specifiying it at the install.
Command line installation:
choco uninstall dart-sdk choco install -y dart-sdk -version 1.11.0To verify you have the right version on your path.
dart --version Dart VM version: 1.11.0 (Wed Jun 24 06:44:48 2015) on "windows_x64"