What can I do differently?

Yesterday I took a lesson, trying to introduce the thinking hats in a real way.
We used this article as our base, and then explored the different hats about this topic.
I used a bus stop activity (students have done this before) and was surprised when they became loud, disruptive, kept fighting with each other and being silly.
We came back together in a circle and tried to go through what people had written for each hat, but it didn't end well.

They had just finished a great lesson beforehand, the best lesson I had ever had with them.
And now...? At the time, to be honest, I blamed them.

I took away from their learning and lectured them about respect and what to do if someone annoys you instead of looking deeper and addressing the real problem.

Was this activity suited to them? Was it a bit too hard? Did I introduce it and explain it enough?
In hindsight, it was probably hard for some of the students. I definitely could have explained the activity more. We definitely needed to break down the article more and discuss its contents more.
I don't want to belittle the students work documented here, but I know they could have done better.

This is not a pity party, woe is me I screwed up type post. It is a learning moment for me.

For next time, I need to remember...

• are my students ready and able to complete this activity?
• what do I need to consider before launching into the activity (e.g. do some of my lower students have the language capabilities to understand this task?) 
• Have I given the students enough background knowledge to be able to use the thinking hats in this way?
• Do we have a good enough understanding of how to break apart an article to use them in this way? What else could I have used? A video?

Update - during the day, I took ten minutes to talk to the students about this reflection of mine.

Referring to our class treaty, (as per my theme of the week!), I talked to the students about how Mrs Sharma and myself are a part of the room 6 team as well, which means we have to take risks, try our best and learn from our mistakes as well (ala the class treaty). The students and I sat in a circle and talked about how maybe I made the activity too hard, didn't explain it well enough etc., and discussed what I could do better next time. The students gave me good constructive feedback. We then talked about with any activity or piece of learning, they can always give suggestions to the teachers for what to do better next time, just as we do for them. The students responded well to this idea, and didn't seem to realize before I said this that teachers aren't perfect and sometimes need help too.

Talking with Archana later on in the day, she congratulated me in doing this - admitted a mistake, being open and listening to feedback, linking to our class treaty. We discussed how it was an important learning time for the students, as it provided a real life example of how to admit mistakes, ask for help and take on feedback.