Millions of children across China have just begun a new school year. Some are going to schools equipped with resources their parents could only have dreamed of - laptops, science labs, sports fields - and some will continue to wow the world on international test rankings. Others go to schools that lack basic resources - or are unable to attend school at all. This disadvantaged group includes students with disabilities, and far too many are being denied an education despite China's legal obligations.

Beijing claims near-universal enrolment for the general population. But China's own statistics suggests that more than a quarter of children with disabilities receive no basic education at all. Among the officially estimated 83 million people with disabilities in China, more than 40 per cent are illiterate and at least 15 million live on less than US$1 a day, underscoring the lifelong consequences of a lack of access to education.

Why are so many children with disabilities not in schools? First, it is difficult to get enrolled - and even those who do so are often asked to leave later on.

Chen Yufei (not his real name) is a nine-year-old with attention-deficit/hyper-activity disorder and an intellectual disability. These conditions, while requiring appropriate accommodation, should not stand in the way of him going to school. Yet, none of his neighbourhood schools would enrol him, because, according to school officials, he would "affect other children". His mother challenged this logic: "Everyone is entitled to nine years of compulsory education, right?"

She's correct: Chinese laws guarantee the right to education for every child over six. The Convention on the Rights of Persons with Disabilities, an international treaty that the Chinese government has ratified, obliges it to provide an inclusive education for students like Yufei. In inclusive schools, all students - those with disabilities and those without - learn in the same classrooms in their communities, and their diverse learning needs are accommodated.

Despite the legal obligations, domestic regulations do not mandate adequate support for mainstream schools to teach students with disabilities. In mainstream schools, teachers and principals receive little to no training, funding or support staff. Because of the lack of government assistance for educators, it is, as one parent put it, "the parent who provides the support". But for the unlucky children whose parents cannot afford to function as their child's pro-bono teaching aide, they often have no choice but to stay at home. As a consequence, often only those with mild disabilities manage to enrol and stay in mainstream schools.

These students face additional hurdles if they try to pursue higher education. The Chinese government requires all university candidates to go through a medical test as part of enrolment. Official guidelines allow universities to deny entry to students with certain physical or psychological "defects" declared or discovered in the test - even if the disability in question has no bearing on the chosen subject. For example, people with hearing impairments are advised not to study more than a dozen subjects, including law and foreign languages. Fearing rejection on the basis of their disabilities, many students choose instead to only pursue the approved subjects. But, sometimes, even that does not guarantee success. Last month, an applicant who uses crutches to walk was denied enrolment to study five programmes in medicine and psychology by a university that he is well-qualified for because "his physical disabilities do not match his chosen subjects".

Children with disabilities can in theory attend special education schools, which exist in parallel to the mainstream system. But these schools not only separate children with disabilities, they are also few and far between. Even if there is such a school nearby, children with disabilities might still be unable to attend.

In the special education system, students are divided according to type of disability - a school for the blind is not going to be useful to a child with hearing impairments, and few schools accept those with autism and other disabilities outside of the official categories. For many families, the mainstream schools are likely to be their only option. But when those schools reject the children, there is nowhere else to turn.

The Chinese government has begun to recognise some of these problems and responded by amending the regulations on the education of people with disabilities. But those revisions do not remove the main obstacles to mainstream education for these children. The government also lacks a consistent plan to move towards a fully inclusive education system, and instead reinforces two parallel systems of education in which many families of children with disabilities continue to have no meaningful choice.

Inclusive education does not have to be costly. For example, assigning ground-floor classrooms for classes that have students with physical disabilities means building modifications aren't necessary. Basic training can ensure that teachers modify their methods for children with disabilities, for example, by providing written notes and facing the class when they speak so students with hearing impairments can keep up.

The Chinese government has much work to do if its classrooms are to accommodate children like Yufei by the start of the next school year. It should revise the regulations to make a clear commitment to full inclusion at all levels of education. It should expand training in inclusive teaching methods for teachers and school administrators, and provide schools with adequate resources to implement them, and it should abolish the official guidelines allowing discrimination on the basis of disability in higher education.

Failure to take such steps means not only opportunities lost for the many Yufeis, but it also tarnishes China's reputation as a country with extraordinary education achievements.