Hi, I am an educator working in an early learning centre. My centre practices outdoor sleeping. I am extremely concerned regarding the children being exposed to extreme heat as they are expected to sleep outdoors unless it is 35 degrees or more. Could you please give me some information to support my concerns, as I am finding this is not good practice and the children are not coping with sleeping in 30 degree weather

Red Nose has no specific information about sleeping babies/children outdoors.
Red Nose does not recommend a specific room temperature for babies sleeping, but recommend dressing baby according to room temperature. Our information is related to sleeping inside.
https://rednose.org.au/article/protecting-baby-from-overheating-during-sleep

Apart from considering impact of general issues like sun, heat & any bugs, I don’t think you will find any specific evidence based information about sleeping children outside.
I’m sure the regulatory issues like Risk Assessment would be needed & regular sleep checks should include if baby/child is too hot, but these issues are best discussed with your local regulators & ACECQA.
Have you checked your Centre’s Policy?
What State are you from?