This link is just out in time for the holidays that links the top STEM toys for kids broken up by age level. If STEM isn't what inspires the kiddo in your life, check out some of the following companies that also sell toys that teach.
Fat Brain is a relatively new company, but have bought from them before and have been quite satisfied. This company also allows you to see where toys are made. This was very important to me when my own children were younger and I refused to buy any toy manufactured in China.
This company has a wide selection of toys for both boys and girls. They supply many art types of activities for all those budding artists out there.
I was just there today and I had to drag my five year old out. They have so many toys to use in the classroom, or at home, that teach everything from music to science to phonemic awareness.
The Cricket Company is known for quality kid magazines, but they also carry a line of gifts as well.