This is exactly what you need to practice formal and informal language with your students. These activities are ideal for grades 3-5 and meet speaking and listening standards (Common Core State Standards SL.3.6, SL.4.6, and SL.5.6).
~Situation Match-Up Cards
~Conversation Match-Up Cards
~Students Recording Sheet with answer keys
~Other Ways to Use Match-Up Cards
~2 Formative Assessments with answer keys
These activities will spark discussion with your students and teach them the situations and conversations that should use formal and informal language.