Parents of youngsters receiving special education services are often concerned about telling their child's prospective kindergarten teacher that their child has received services through Early Intervention or CPSE. Early intervention services did what it's supposed to do and their child is now ready to go into a regular class, but parents are uneasy about sharing the history of special needs. They fear that if the teacher knows that their child once needed additional help, their child will be stigmatized in some way and that the teacher will look for problems that aren't there. This is especially true in the NYC where parents are knowledgeable and wary.
In my experience this concern is unfounded if understandable. Teachers are much more concerned with how a child is functioning now than what they needed in the past. If the parents were proactive enough to get early intervention services, that's positive. In addition, there might be some residual weakness that the teacher should know about so that teaching is more effective. For instance, if there was a receptive language issue, the teacher would double check to see that the child understands the classroom directions. If auditory processing is slow, the child may need extra time to respond to a question. If OT was needed, the child might still benefit from a special pencil grip which could be put in place from the beginning of the year to limit frustration.
In short, when a child has or is still receiving some kind of services, it's a good idea to let the teacher know. The teacher and child will only benefit from the sharing of this knowledge.