Can anyone tell me whether children with SEN in main stream schools can choose any school when applying for secondary school or whether they have to have a specific reason for going to particular school? Thank you
If the child has an EHCP that names a specific school, then they will get a place at that school.
If they don't, then they apply to any school they like, as normal through the regular admission channels, and their application will be viewed using the normal admissions criteria for each school. Schools will quite often have a "medical or social" criteria, under which you would need to provide evidence that the pupil needs this specific school if you want a particular school but don't have an EHCP.
There is one other exception. Sometimes a school has a "unit" or "base" for a specific SN and then a child may get in to the school with the relevant "unit". For example there is a school near me with a "visually impaired base" so visually impaired pupils get in on the "base's" admissions criteria and are extra to the school PAN. It works similarity for another school and ASD.