I plan to make a birthday present for a six year old girl, friend of DD. It is a bit difficult, since she does not have that much "natural" toys, it´s basically all plastic.
Last year I made my kids aprons and wrapped them with a pack of cake sprinkles. Both my 6 year old DD and 3 year old DS loved them. A pack of silicone cake cases would be good with it too.
The eye spy bags have also been well used. They are not something the kids seem to get out a lot at home but they have kept them busy in many a waiting room
Accessories for her doll are fun - simple clothes, a sling, diapers, a quilt and pillow, sleeping bag etc.
She might like a matching pillowcase dress - one for her, one for her doll
Adventure bag (just a messenger bag) with a bug collecting jar, magnifying glass and a small sketchbook or field guide (and a promise of a hike).
An art carryall - there are tutorials all over the web- they basically have a place for crayons or pencil crayons and a sketch book
A fairy house making kit - lots of natural bits, a small bendy doll fairy in a storage basket
I'd peruse One Pretty Thing for ideas!