6 year old birthday gifts

What have been big hits for 6th birthday gifts? Our son wants for nothing (we are blessed with a lot of gently used items), and his birthday is coming up. Today, his nana asked him what he wants most, and he said “batteries” (because his walkie talkies eat them like crazy so we stopped buying them). He plays no video or computer games.

The theme of his party is art, but he already has so many art supplies! We have a membership to the local children’s museum as well, and the nearest zoo is free to all guests.

Thoughts?