One of CS First's newest offerings is a module that teaches you and your students how to "Create Your Own Google Logo" like the Google Doodles that change daily on Google's search page.
The module starts with a plain Google logo and then takes you through a number of ways to modify it and make it more interactive, just like the daily doodles do.
All of the coding is done in the Scratch editor and if students have accounts, the projects can all be saved and modified later.
According to Google, the project should take about 30-60 minutes. This is highly dependent upon the user's previous experience in Scratch though.
The activities are a great way to use the CS First resources without committing to the full curriculum.