Inspiration is a big concept for kids to comprehend. My kids just completed their final class book and wrote about who inspires them. I received responses from moms to Martin Luther King, Jr. to our principal to sharks. All of them could justify how those people were something they aspire to be.
I stole an idea from my neighbor teacher (she's phenomenal- what I want to be when I grow up). She put pictures of famous architecture out with her block station to inspire the kids with ideas of what they could build. Of course, we encourage them to create something, but this gives them ideas to spark that creativity.