Susan, your Materials palette is kind of “closed”. Do you see it? To change the color of the text, it is exactly the same way to change the font or the size: highlight the text and then, change the color in the Materials palette. The “top swatch” will change the outline of the text (if it is not set to a width of 0) and the “bottom swatch” will change the fill of the text.
Let me know if that helps.