Updated 2020-11-27

Happy to see that SourceTree allow users to skip the login procedure in version 3.3.9.

For older versions:
SouceTree uses accounts.json file to store account settings.
It would skip the login process if there is an accounts.json file in your machine.
So you can copy the accounts.json file in %AppData%\Atlassian\SourceTree\ to any other machine to skip the login procedure.

I don't think SourceTree allows to install without using an Atlassian Account. I've also tried and couldn't make it.

Have a look at Github Desktop, I think it allows not to configure an account https://desktop.github.com/

(I also prefer the UI from what I've seen - CLI still rules)

Edit: keep in mind that's easier for the students to google by themselves solutions to problems with git using the CLI than using UI apps

Thanks to Mike for mentioning the version of SourceTree that did not require a login.

It's possible to install SourceTree v1.6.4 which does not require a login to an Atlassian acount.

How to install SourceTree v1.6.4 for Windows

How to install SourceTree v1.6.4 for Windows

This gist shows how to install SourceTree without having to login to an Atlassian account.

Later versions of SourceTree after v1.6.4 require a login to an Atlassian account.

Steps:

• Install Chocolatey
• Install SourceTree 1.6.4 using Chocolatey

Install Chocolatey

• Run Windows Powershell as Administrator
• Run the following command Set-ExecutionPolicy Bypass; iex ((New-Object System.Net.WebClient).DownloadString('https://chocolatey.org/install.ps1'))

Install SourceTree Using Chocolatey

Run the following command within an administrative console/terminal/powershell.

choco install sourcetree --version 1.6.4

References

• Install SourceTree without an Atlassian account?
• SourceTree 1.6.4
• Installing Chocolatey