Google Learning Center - This is a great place to learn how to use Google Apps. Scroll down to the "Learn by App" section and click on the app you need help with.
11 things you need to know about the redesigned Google Drive - Google Gooru
How to create videos in Google - Educational Technology and Mobile Learning
Google Cheat Sheets - The best Google resources by Kasey Bell at shakeuplearning.com
Everything you need to know about Google Classroom and then some!