What are you wanting to achieve with the IEP? Are you looking for instruction in areas your ds has a challenge in, instruction outside the scope of the classroom in areas of strengths (gifted/accelerated), or are you looking for accommodations that will help minimize the impact of his ADHD an enable him to fully access his curriculum at school? An IEP would be used to give individualized instruction in areas where a child has challenges or is falling behind, in *some* school districts children who are identified as gifted may have IEPs or other types of individual learning plans but this varies by school district, and accommodations such for ADHD/etc that do not involve direct individualized instruction are usually made through 504 plans if they are individual enough they aren't already a regular part of the classroom environment.
Re the 0s and 1s on the ADHD questionnaire vs the notes on the report card - we've had a similar situation with our older dd. I think the thing to remember is - the report card gives you information that can be used to help your child be even more successful in the classroom than they already are, and many children are distracted in a classroom setting, it's not necessarily something atypical. The ADHD questionnaires are attempting to summarize atypical behavior - so distractibility noted as a concern there (from a teacher's perspective) would be distractibily beyond what the child's age-peers are distracted by in the classroom. FWIW, my dd is easily distracted and will admit it! Most of her friends appear to be easily distracted in the classroom too - but it doesn't look like the type of distraction you get with ADHD... but it does interfere with schoolwork and is something I am not surprised to see appear on a report card

polarbear