I think this can be used across grade levels and it works REALLY well with younger kids. You (or students) can create teasers around lessons, experiements, concepts, etc. You have enough discussion or introduction to spark students curiosity. Students will be itching to know what's next, but you build the excitement by not disclosing too much. If you build this up, especially with little guys, they will be into it! I once asked my students, "Do you know what might have really happened to Henry Hudson? It's kinda creepy and ties in with CSI." The majority of students started digging and trying to figure it out when they got home. Couldn't wait to hear more.