PBL: Reflections on our current teaching practice

One of the teaching strategies that I use most commonly is fostering students' control of their own learning. Students are encouraged to plan, execute, monitor and repair every communicative activity they take part in.
I facilitate learning most of the time in the classroom.
Students take active part in communicative activities most of the time.
I feel my current approach can be complemented with a PBL approach.
Students revise continually and use what they learn in different contexts.
I already use PBL approaches. Aligning contents and competences and assessing individual work are difficult points.
I find out about my students' needs talking to them and when assessing what they do.
To experiment PBL, I choose my four classes and the topic How about...? (Groups of students meet up outside the school to do a leisure activity of their choice).