It actually said things like "How do you *feel* about the number 15?", I kid you not.
I don't know a thing about New Math, but there is such a thing as Synesthesia, where people associate smells, tastes, feelings and sounds, among other things, with numbers, letters, colors or words. A person with synesthesia might very well "feel" something about the number 15. It's not a common phenomena, though.
When my son was in kindergarten he mentioned to us that 'E's were green, "Es are always green". The hubs though the kid was displaying synesthesia and got so excited, but it turned out that whenever the teacher pinned letters to the bulletin board at school, each letter was a different color and the Es were quite literally green. False alarm.