Hmmm it is no wonder us teachers get bad names, when there are some teachers out there that treat students like this. A teacher has no right to talk to a student like this ever, it is unacceptable, and if it happened to a child of mine I would be in the principals office demanding an explanation.
Dyslexia is something that is VERY difficult to test for, I have had a couple of students over the few years that might have been dyslexic, but like I said it is so hard to find out for sure. There could be some other explanations including some sort of processing disorder.
Now I am not sure what state you are in, but I know that we have to have some very very firm reasons for excluding a student from an excursion, and the fact they can't memorise a poem would certainly not wash as a valid excuse in any school I have ever worked in, so if I were you I would not be accepting that.
Country school or not every school has to cater for a student at the level they are at, if they are what we term as SAER (student at academic risk), be it because of learning difficulties, attendence, behaviour, or being especially clever, then if is our job as a teacher to write a special plan for the child stating how we are going to assist that child to meet their learning targets, we meet with the parents to discuss it with them, and we review them periodically.
As for getting assitance, all schools should have access to a school based pysch. who can arrange for testing and, and then help to access any other services you may need.
Remember that you have to be your child's advocate, a good education is the MOST valuable gift you can give to your child, so do not take this laying down- keep going back until someone starts to listen. If he does have some sort of learning problem, the sooner it is recognised the sooner strategies can be put into place to help him learn in a manner appropriate to him.
And most of all give your baby a great big hug and tell him how special and clever is his, and make sure he understands that no one should ever make him feel bad about himself!
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