Common Core Standards
Grade 4
Speaking and Listening SL.4.6
Differentiate between contexts that call for formal English (e.g., presenting ideas) and situations where informal discourse is appropriate (e.g., small-group discussion); use formal English when appropriate to task and situation. (See grade 4 Language standards 1 here for specific expectations.)
Calling all code-switchers. You've probably heard of code-switching when it comes to your bilingual students, but it's a gift that we can all activate. We need all students to be able to switch between formal and informal speech. Plus it helps in understanding different writing styles in literature as well.
Teaching this standard is a lot like teaching students that talking to their friends is different than talking to their teacher. It comes intuitively, but slip-ups happen. Send your kids signals about what kind of speech is acceptable. For example: during a presentation, don't call us your bros. Thank you very much.