Not solely an SEN/disability issue, but a topical one.
It can be extremely easy to work out which school a child goes to from a photograph of them in school uniform. Sometimes there’s a logo that gives it away. Sometimes local knowledge of the schools in the area combined with a less clear picture is enough. Sometimes it takes a little more effort to complete the jigsaw, but it can be very easy.
Primary school pupils old enough to travel independently and secondary school pupils are more vulnerable to attempts at grooming than younger, more closely supervised, children.
Children who can be identified as attending special schools will be particularly vulnerable.
Best to keep your photographs of children in school uniform to those you know well enough to invite into your home / who you’d tell, if they asked you, which school your child was at. This may well be a subset of the people you interact with online.