During a number talk, students are thinking, asking their peers questions, and explaining their own thinking all while the teacher records the thinking. Sherry Parish has written the book Number Talks (Amazon affiliate link) and it offers awesome ideas for Kindergarten to 6th grade. It is definitely an expensive (up to $60 if bought new) but offers great ideas and real-life examples of Number Talks.
noun. Avalanche warning signs. Avalanche warning signs. The definition of avalanche means a massive quantity of something that comes suddenly such as snow, ice, earth or rocks that come loose and speed down a mountain. 1  An example of avalanche is a glacier that splits from a cliff face and hurdles down the side of a mountain.
earthquake. n. 1. (Geological Science) a sudden release of energy in the earth's crust or upper mantle, usually caused by movement along a fault plane or by volcanic activity and resulting in the generation of seismic waves which can be destructive. sudden movement of the Earth's crust. Earthquakes are caused by the release of built-up stress within rocks along geologic faults or by the movement of magma in volcanic areas. They are usually followed by aftershocks. See Note at fault.