DD8 could locate most countries of the world and knew many, many flags at age 2. She retained some major/easy stuff, like Australia, Russia, China, Spain, but has definitely forgotten countries like Ghana and Turkmenistan. I wonder if she retains ANY flags...probably not. I feel confident that she could easily relearn it all if she wanted to.
She started learning bird species at 18 months. These are largely retained, but the difference is that she is still very interested in birds and reads and uses field guides.
I have noticed that she still knows a lot about the planets, but I think this has been periodically reinforced at school.
Both kids picked up all the state nicknames when we were playing Scrambled States of America a lot last summer. I bet they're forgotten now.
