R.L.
Hi M.,
Is your son getting speech therapy through the school? If so, talk to his therapist about testing for visual processing problems. You might try talking to the school psychologist and counselor, too. Sometime you have to force issues like these with the public schools -- they don't want to have to pay for services if they can avoid it.
You're right to look into this as early as possible -- trust your instincts as a Mom. It is true that reading readiness is highly variable, but by 5 1/2 your son should be able to recognize letters even if he hasn't yet gotten the idea of how to blend them into sounds. Can he recognize other shapes, numbers and symbols consistantly? If not, this would be a good indication that this is not just a reading readiness issue and that there is a true visual processing issue. The earlier you catch it and treat it, the greater his success will be in the long run. Scholastics are just a part of the picture. Over time if your son can't keep up he could get increasingly frustrated, his self-esteem could be effected and he could start to think of himself as stupid or not as good as the other kids. This could start happening way before 3rd grade. I used to help out in my kids' classrooms. It was clear that by first grade kids classified themselves and others according to their academic abilities. Slower children were teased for being dummies (we would put a quick end to that) and one very sweet and brilliant ADD child was friendless because the other kids couldn't tolerate his behavior.
I highly recommend you check out the books by educational psychologist Mel Levine and the website allkindsofminds.com. Push to get the testing done. If you can't get the school to do it, find a reputable private educational psychologist to do preliminary testing. With some results in hand, you'll have greater influence for insisting on testing from the school. Consider this: the best that can happen is that no problem is found and your child is a late bloomer or one who might just need a little bit more tutoring. The other best that can happen is that your sweetie has a problem that can be diagnosed and helped. Either way, he wins.
BTW, I do not recommend putting your child in a school that has a lower academic standard. That will not help him in the long run, but will only put him further and further behind as he progresses through school. Whether it's fortunate or not, college admissions are highly competitive and kids from better schools can end up with better opportunities.
Good luck with this -- I hope everything turns out well.
R.