Management tricks

I am a new substitute in a large, urban east coast district.
The post concerns a non-verbal management trick I developed after my first day subbing. The tactic involves a set of laminated signs in large black lettering visible to the entire class. The signs read:

1 Please quickly and quietly take your seats.
2 Please be seated and direct your attention to me.
3 You have 5 seconds to be seated before I call the office...
8 I will now call the office for staff to come and restore order.
9. Thank you for being seated and attentive.

I have only used the signs once. The situation in which I make use of the signs must be one in which a. Many different students are enaged in consequential of-task behavior (the vast majority in the class). b. Several other less heavy-handed strategies have been attempted. c. The learning environment faces immediate threat of disintegration or there is an emerging physical risk to students. Finally, I will not use these signs with students below grade 5.

I would love to hear people's thoughts about these tactics. Are they good, bad indifferent? Or can I modify them to be more effective? Am I using a coercive method and not realizing it? Thanks.

Most schools have their own class managment signs up in the class rooms. Most Substitute teachers need to reinforce them to gain respect in the classroom

Signs are cool but don't you need to say something too? I think they need to hear your voice in order to get the urgency of your message. Without the voice, it sounds cold and distant-.

Why not just beg,plead,explain or give a choice; be quiet and attentive facing the wall {seated] or take a trip to council. [only age 14+]

I observed a teacher teaching in an inner city school classroom who sat on his situation in an awesome way. Me, I struggle but am progressing from novice-passionate to a beginner-advanced level of classroom management ability. I like the sign idea. There are some inner city classrooms that need the call to attention, a reference for when the principal and or security removes them from classrooms, and an answer when they are made to adhere to classroom rules in the absence of their regular teacher. Thanks for the post. Euroclydon/ lad/ 2007