Post the letters A, B, C, and D in 4 different corners or locations around your classroom. Ask multiple choice questions and have students move to the letter that represents their choice. If possible, post the possible responses and which letter they go with. The types of questions you use can be anything from low-risk/playful questions to more challenging content questions, or even student-generated questions. When you reveal the correct answer (if there is one) is up to you as well. To foster collaboration, you could have students work in pairs and discuss before moving to reach an agreement on where they are going to go. If students have limited mobility for any reason, you can give that student the letters A, B, C, and D on different pieces of paper, and once they reveal their response the students from that corner can gather around them if they need to discuss anything.