Middle school is a very different matter for sure! My oldest is in K, so yeah, no idea of the upper levels. It would surprise me if a US school would undo a US grade skip. It'd be different if you were switching from US to UK, for example.
Our school also has a significant portion of non-native speakers, but it's not at all the same as a local school with non-native speakers. The top girl in D's grade who he reads with is not a native speaker. She's better than all the US/UK/Ozzie kids.
It doesn't have to be tears! Moving abroad has been the best experience for my family. My kids are extremely happy, though it's all they know.
Tell them about the new adventures you'll have. Look up your new location on the map and show them pictures of what things are like there. Emphasize what you're going to, instead of what you're leaving from.
Good luck!
