One in seven children struggles to write his or her own name after a year at primary school, show official figures.
The Government analysis of 556,000 children showed that almost 80,000 five-year-olds struggle to hold a pen properly or form basic words such as "mum", "dad" and "cat".
Thousands more cannot say the alphabet or count to ten.
According to the research, some 14 per cent had problems with basic writing, meaning they could not spell their first name and compose a simple shopping list or letter to Father Christmas.
Eleven per cent could not say the alphabet. Nine per cent failed to understand that addition meant counting two different groups, while three per cent could not count to at least 10.
"These disturbing figures show that the department have missed their targets and children are falling back in almost every area of development," Telegraph quoted Maria Miller, shadow families minister, as saying.
"It is unacceptable that the Government is still failing to give children, particularly from the most deprived backgrounds, the best start in life," the leader added.