The first school trip that Annette Masson's son was prevented from going on came in P7, when his classmates were due to go skiing.
"He has autistic spectrum disorder and ADHD," Mrs Masson said. "In November, the depute head said if he behaved until April, when they were going away, he could go on the trip. I found that very unfair and I said I'd rather he didn't go than be heartbroken over one mistake."
Now he is in S3 at a council secondary in Aberdeen, and this summer his classmates will travel to Barcelona for a week. However, the school has refused to allow him to go, even though Mrs Masson offered to join the group.
Alternative activities had been offered, she said, but it was important that he went, to allow him to bond with his peers.
New legislation due to come into force this autumn could give parents like Mrs Masson more power.
Schools currently have to ensure that their policy, procedures and practices are inclusive. But, under the Equality Act, they will also have to invest in extra staff and resources "where reasonable".
According to experts, the changes will have an impact on every aspect of school life, from the netball team to the chess club.
But school trips were the most likely battleground, according to Iain Nisbet, head of the Education Law Unit in Glasgow, which is funded by the Equality and Human Rights Commission.
Calls from parents seeking advice after their disabled child had been excluded from trips were common, he said.
Mrs Masson said: "These children have enough to put up with in life without being excluded from the positive experiences schools have to offer."
Aberdeen City Council insisted the school was inclusive, and that pupils with a range of additional support needs had been taken on trips in the past. "These decisions are based on a risk assessment and meetings with the pupils, families and senior education staff," a spokesman said.
However, Mr Nisbet suggested authorities would have to go much further to comply with the new law, as it affected disabled pupils.
"At the moment, the legislation contains a reasonable `adjustment duty', but it does not require auxiliary aides and services such as extra staff or resources," he said. "The new legislation stipulates that this must be done `where reasonable', to ensure disabled children are not placed at a disadvantage."
The change in the law could also prove "significant" for independent schools, Mr Nisbet added. While exempt from the Education (Additional Support for Learning) (Scotland) Act 2004, under the new rules they could be forced to increase the support they offer to disabled children.
"Independent schools will have to increase their provision for disabled pupils to make sure they are able to access the curriculum on an equal footing," Mr Nisbet said.
The cost implications of the act were difficult to predict, he added, given that only "reasonable" steps could be demanded of schools.
But Ken Cunningham, general secretary of School Leaders Scotland, suggested any extra costs would be a burden on schools in the current economic climate.
And Leslie Manson, president of the Association of Directors of Education in Scotland, said "one person's reasonable adjustment is another person's unreasonable expectation".
EQUALITY PUT SIMPLY
Disability legislation has already forced one school, Crown Primary in Inverness, to cancel a P7 trip to an outdoor centre after a parent complained that her disabled daughter would not be able to take part. Donna Williamson said her daughter was physically unable to go kayaking or to fire a bow and arrow. The trip has now been rescheduled for next month.
The new legislation stems from Labour's 2005 general election manifesto commitment to introduce a "single act to modernise and simplify equality legislation".
The Equality Act, due to come into force in October throughout the UK, is the result. It is a weighty tome which brings together everything from the race relations acts of the 1960s to the sex discrimination acts of the 1970s.
It also introduces a range of new obligations, such as a mother's right to breastfeed her baby in public and a compulsion on employers in large organisations to publish the pay disparities between men and women.
In terms of education, it ensures that schools cannot discriminate against pregnant pupils or new mothers. And it imposes a legal duty on public bodies, like schools, to promote homosexual and transsexual rights.
The legislation was beset by fierce controversy as it was steered through the Westminster Parliament by Harriet Harman, Leader of the House of Commons and Minister for Women and Equality.
Pope Benedict XVI raised the stakes in February when he urged Catholic bishops in England and Wales to fight the then Equality Bill with "missionary zeal". Religious leaders have expressed concern that the new law could force churches to employ gay people and transsexuals when hiring staff other than priests and ministers.