We have school supply drop off and meet the teacher day in our school. For both the kindergarten year and 1st grade, I went in and mentioned to the teachers that my DS7 was advanced but he was lacking social skills and may cause trouble if he was not occupied with some challenges. I did it really briefly just to give the teacher some warning. Then after a month or so I contact the teacher and ask how everything is going and then I get into more detail about his giftedness.
Just found out yesterday that DS7 is having the same 2nd grade teacher as my older DS. She met him a couple of times and was very impressed with what he already knew when he was in kindergarten. So I think she may already have some ideas what he's capable of. I am planning on having a brief conversation with her and see how much she knows about DS7 (the principal may have already informed her about my DS7 as I have been advocating for acceleration since 1st grade) and we will go from there.
