This can be downloaded from here. Unzip and run the jupyter-scala.ps1 script on windows using elevated permissions in order to install.
The kernel files will end up in <UserProfileDir>\AppData\Roaming\jupyter\kernels\scala-develop and the kernel will appear in Jupyter with the default name of ‘Scala (develop)’. You can of course change this in the respective kernel.json file.
Click through to see how to install a few other kernels with various levels of configuration.