Favorite/best elementary school grade?

I'm a senior in high school and this year I'm taking a teacher cadet cl. In this cl we basically learn about learning styles and child behavior. The last nine weeks we have to intern for an elementary cl during our cl period. I'm planning on doing my internship at my former elementary school but a lot of my old teachers have gone. So my question for parents, teachers, etc. is what grade did you find most entertaining or attentive? You know, a grade where they were excited about school? :) Thanks for any feedback