"Matt O'Connor, founder of campaign group Fathers For Justice, said: "I'm astonished at this. It totally undermines the role and significance of fathers whether they are still with the child's mother or not."
By Simon Johnson, Scottish Political Editor
Last Updated: 8:44PM BST 22/06/2008
Thousands of primary pupils were prevented from making Father's Day cards at school for fear of embarrassing classmates who live with single mothers and lesbians.
The politically correct policy was quietly adopted at schools "in the interests of sensitivity" over the growing number of lone-parent and same-sex households.
It only emerged after a large number of fathers failed to receive their traditional cards and handmade gifts.
Family rights campaigners last night condemned the policy as "absurd" and argued that it is marginalising fathers, but local authorities said teachers need to react to "the changing pattern of family life".
An Office for National Statistics report in April found that one in four British children now lives with a lone parent - double the figure 20 years ago.
The Father's Day card ban has been introduced by schools in Glasgow, Edinburgh, East Renfrewshire, Dumfries and Galloway and Clackmannshire.
Tina Woolnough, 45, whose son Felix attends Edinburgh's Blackhall primary school, said several teachers there had not allowed children to make Father's Day cards this year.
Mrs Woolnough, a member of the school's parent-teacher council, said: "This is something I know they do on a class-by-class basis at my son Felix's school. Some classes send Father's Day cards and some do not.
"The teachers are aware of the family circumstances of the children in each class and if a child hasn't got a father living at home, the teacher will avoid getting the children to make a card."
The making of Mother's Day cards and crafts, in the run-up to Mothering Sunday, remains generally permitted.
But the Father's Day edict follows a series of other politically correct measures introduced in primary schools, including the removal of Christian references from festive greetings cards.
Matt O'Connor, founder of campaign group Fathers For Justice, said: "I'm astonished at this. It totally undermines the role and significance of fathers whether they are still with the child's mother or not.
"It also sends out a troubling message to young boys that fathers aren't important."
Alastair Noble, education officer with the charity Christian Action, Research and Education, said: "This seems to be an extreme and somewhat absurd reaction.
"I would have thought that the traditional family and marriage are still the majority lifestyles of people in Scotland. To deny the experience of the majority just does not seem sensible."
Local authorities defended the change, saying teachers needed to act "sensitively" at a time when many children were experiencing family breakdown and divorce.
A spokesman for East Renfrewshire Council said: "Increasingly, it is the case that there are children who haven't got fathers or haven't got fathers living with them and teachers are having to be sensitive about this.
"Teachers have always had to deal with some pupils not having fathers or mothers, but with marital breakdown it is accelerating."
Jim Goodall, head of education at Clackmannanshire Council, said teachers are expected to behave with common sense but be sensitive to "the changing pattern of family life."
South Ayrshire Council said children should not feel left out or unwanted, while City of Edinburgh Council said the practice on Father's Day cards was a matter for individual schools.