Sorry to hear you got some negative feedback Steffelz. Should anyone else say this to you, ask them for clarification, you have the right to know what can be improved, and perhaps the person there was just having a bad day
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Different things work for different age groups. I work with 3/4 year olds in a school based Kindy. If the children are on the mat and seem a bit distracted I use the following
Roly poly roly poly up up up (rolling my arms over each other upwards)
Roly poly roly poly down down down (opposite)
Roly poly roly poly clap clap clap (doing 3 claps when you say the words)
Roly poly roly poly lay them in your lap. (hands in laps)
By the end of this all eyes are on me and hands are in laps.
There is always the follow me technique where you say hands on heads, hands on shoulders or any other body part and lastly hands in laps or on lips.
Sometimes I just start a song, by the end of the first line children are singing with me and others join in very soon after.
OPther times I ring a bell and the children become statues, I praise them of course and use this time to explain that 'in 5 minutes we are packing for lunch' or whatever it is I want them to know.
Remember for some kids sitting for a long time is something they are not developmentally ready for - give them a chance to wiggle if they need it.
Watch others and see what they do, we can learn so much from one another. Be confident in yourself and it will all start to fall into place.
We can all always improve. I find that after lunch my children struggle to sit on the mat anywhere near as long as they need to in the morning so I allow for this and make things short and sweet.
Also, my kids love story books on CD. See if they have any at your centre, you just have to hold the book and the children will settle so they can hear the voice on the cd reading the story.
Good luck
CAthiek