For my nephew's 4th birthday this year he and I went on a "secret expedition". I took him to the toy store and told him could pick out 2 toys.
We spent some time looking around and he selected this robot. I looked for the age limit and it was for 6 and up, I explained that it was too old for him but he assured me it is OK.
I explained to him why it was important and he said "OK tsha, I don't want anything for more than 4 years old". And as he continued to look for his 2 toys it was the first thing he looked for when he looked at a toy. Some he really liked but he put them back without me saying anything telling me "tsha that's too old for me".