I'll be spending a weekday afternoon at the City Museum with my 3-year old and want to have dinner afterward somewhere relatively closeby. My daughter is well-behaved but active, and we like good food. American or any ethnicity is fine.
You should go to 10th Street Italian. It is very casual and the food is terrific. It is on 10th street, just off of Washington, within walking distance from the City Museum. You can stop for gelato on the way back. Have fun.