This type of thing shouldn't ever happen! It's avoidable...
If the teacher was busy and didn't notice, there should at least be some people paid to just be at the school gate just incase. If anyone was stationed at that gate, they would have returned the child back to his class with no one even knowing anything like that happened. 
Shocked mum couldn't believe her ears when she heard her 4 year
old son who was supposed to be at school, knocking at the door and calling her to let him in.  He had climbed down the window of his classroom without his teacher noticing, walked alone on a busy road to get home. She calls the school with the teacher not even
realising that one pupil has left the class unnoticed. 
Her story...

Mum Claire Frost couldn't believe her ears when she heard her little boy yelling through the family's letterbox "mummy please let me in".

And she has been left enraged after calling the Holy Trinity Nursery in Taunton, Somerset - with teachers not even realising her son had vanished.

The 32-year-old said: "I felt sick to my stomach when Connor showed up at the door.

"I couldn't believe what was happening." The nursery has since apologised, saying a number of changes had been implemented - including adding combination locks and adjusting windows.

The mother-of-four said she has taken Connor out of the nursery since the incident as she does not trust it to look after him.

She added: "He's four-years-old. He could have been run over on the main road.

"My heart was racing when he came to the door. "He burst into tears as he thought I would be angry at him but I wasn't. I was angry at the nursery."

The mum said: "I'm just really frightened that something more serious could have happened as a result of the incident."

Jeremy Handscomb, head teacher at Holy Trinity Primary School, where the nursery is based, said: "This incident should not have happened and we apologise without reservation.

"This is a recently built and purpose-designed nursery provision and surrounding outdoor site which met all the health and safety requirements and building regulations and had up until Monday ensured the safety of all children.

"In the light of this incident and following an investigation we have immediately made some additional alterations to the safeguarding of the building and the wider area."

At this age, these kids are so full of energy and adventurous, just keep and eye and God help us.