Chrome //
Extensions 
Chrome
Web store 
Trelson Assessment for Google Classroom
Trelson Assessment for Google Classroom allows you to use Classroom to support the formative post work of an assignment.
Ouriginal for Google Classroom Extension
Ouriginal integration for Google Classroom™ allows teachers to send student submissions to Ouriginal for text-matching analysis.
BookWidgets Google Classroom Integration
This extension integrates BookWidgets into Google Classroom.
Audio Recordings for Google Classroom - Beep
Allows teachers and students to leave voice notes and feedback on Google Classroom, Gmail, Google Docs, Slides, Forms, and Sheets.
Random Student Generator for Google Classroom
Select a random student from your Google Classroom at the click of a button - keeping students engaged in learning.
Google Classroom Grades Filter
A simple(r) way to filter assignments in your Google Classroom Gradebook
