My colleagues and I use a variety of hand signals in our classroom to avoid unnecessary disruptions and maintain focus and time on task. Three common hand signals: a signal to use bathroom; a signal for needing scrap paper; and a signal for asking a presenter to speak louder. We introduce all of the hand signals to students at the beginning of the year in a community-wide Town Hall Meeting.
Anytime I can bring a student up for a demonstration it usually captures the other students' attention much more than I do. Having a physical connection can help with internalizing the mathematics.
Even with the best set of directions students still needed some guidance or individual assistance. My school currently uses a full inclusion model (Special Education students are included in the general education classes) and SPED students often need additional support. I want all my students to learn to be independent and take ownership of their learning but I also do not want them to "suffer in silence" if they need help or are incapable of access the material. Having a co-teacher adds an extra set of hands and eyes to the classroom and gives my the flexibility to even create multiple classrooms within the class.
During an Independent Learning Zone session, every student in my blended classroom is working independently on a different set of problems. It's impossible for me to be an answer key for 25 different students doing 25 different problem sets, so I print out their respective answer keys in advance and give each student his or her about 5-10 minutes into the period. This empowers them to monitor their own academic performance and self-correct as they are completing their assigned task.