We have selected a few websites and books that can help you on your first steps into PBL. They can be very useful in enlightening some of the key concepts and also providing ideas to begin working with it in the language classroom.
Edutopia - this education portal offers a variety of articles about driving questions
Rubistar - a tool that helps teachers build rubrics
Teachers First - article that explains some of the different types of rubrics https://www.teachersfirst.com/lessons/rubrics/what-are-rubrics.cfm
Ideas for projects
Buck Institute of Education - This is one of the most important websites on the topic, on which you can find everything related to PBL, from articles to project ideas
Project-based Learning Applied to the Language Classroom - Juliana Tavares and Louise Potter
In this book, the authors present the main concepts involved in PBL from the foreign language teacher stance. They also present sample projects for students in the primary and middle education that can be easily adapted to all levels and ages.