Rod and Emma Hughes, of Kings Mead, Puddletown said they were shocked to hear the school may close after being open for 13 years.

Their son Jacob, five, who has attention deficit hyperactive disorder (ADHD), autism and speech difficulties, attended the school.

Mrs Hughes said: “The school is life changing, essential and vital.

“It would be heartbreaking if it closed.”

The couple credits the group with diagnosing Jacob’s condition and their elder son Harry’s ADHD and Asperger’s Syndrome.

Harry, eight, won a place at the group but due to family circumstances at the time was unable to attend and went into mainstream education.

Mr Hughes said that the family wished Harry had been able to go to the group and benefit from their support.

He said: “We are lucky in a way because we are a textbook example of why the group shouldn’t close, as Joseph went and Harry didn’t and the difference is noticeable.”

He added: “It would be criminal, immoral and diabolical if such a place was allowed to close because of lack of money.”

Ex-pupil Yasmine Wild, 11, is now doing well at Dorchester Middle School.

She was born with mild brain damage.

Her mother Ruth Wild of Littlemoor Road said: “I’m positive that if it wasn’t for the opportunity group, she wouldn’t have been at the school and probably wouldn’t be the child she is today.”

She added: “In the long term, these children are our future and given a chance they can make a difference too.

“How are they going to learn if you shut a wonderful place like that down.”

Helen Walker, 25, from Littlemoor is one of the parents.

Her son Phoenix, eight, has Angelman’s Syndrome, a neuro-genetic disorder characterised by delayed development.

Mrs Walker, said: “He has the cutest little smile.

“Children with the syndrome are often described as angels because that’s what they look like.”

She added: “They can’t close the group, too many people will be left with nowhere to go.

“It is such a huge amount of money and it is really hard but we are hopeful.”

If you would like to help with the appeal call Dorchester Opportunity Group on 01305 751707.