I know that the district here claims that once the child is in the average range academically that they have no further responsibility to do anything other than what is offered in the general ed classroom. The average range starts at the 16th percentile.
If a child is identified as gifted (using the CogAT in 3rd grade and the cutoff changes every year it seems), then at the beginning of the year the classroom teacher and the parents make a plan to challenge the child in the area of giftedness (apparently one can only be gifted in reading and math). These plans usually include being allowed to use a computer program for math (like EPGY) or reading more difficult books for book reports. No differentiated instruction and no acceleration.
I wouldn't bring up giftedness in this meeting. You're going to need evidence--testing, obvious academic success in the classroom, something--or they're just going to blow you off (they may try to blow you off even if you have all the evidence in the world; in our district the only "evidence" they'll accept is the CogAT which is not very reliable at identifying gifted kids, especially 2E ones).
I'd keep the topic of the meeting focused on how the teacher can help your son with his sensory and attention issues in the classroom (and any therapies he might receive) and then give it a few months to see if things are better. In the meantime, you can research your school's policies on differentiation and acceleration and what the status is of their gifted program.
Oh, and above all, never use the word "bored" with school personnel!
Good luck!
