I love to use a lot of collaboration with groups in class, with lots of talking opportunity. In my experience, this sets an environment of comfort very early on, so students are more likely to try things, and usually have limited student troubles because it allows me to monitor work more quickly and easily, and small groups is a safer space to learn. Many students learn well from trusted peers, but I also believe math is best learned when students can immediately determine their accuracy. Frequent teacher checks during formative assignments provides immediate feedback and correction (if needed), and encouragement for a job well done, which gives confidence to continue tackling challenging problems. It's best to catch mistakes before they are habit! Scaffolding and easy self-check activities are important for building fluency.