Very dull or boring. Everyone loves that period drama, but, to me, it's as exciting as watching paint dry. Rachel fell asleep during the big game because she thinks that watching sports is exciting as watching paint dry.

To cause one to feel enthusiastic about something, especially in anticipation of participating in it. In this usage, a noun or pronoun is used between "excite" and "about." Despite my best efforts, I still haven't been able to excite my students about trigonometry.