Identify three common environmental factors children might encounter that impede brain development and share how that might affect the classroom environment

Two paragraphs with at least 100 words per paragraph explaining the following which should include a reference for each individual paragraph.
1.  Identify three common environmental factors children might encounter that impede brain development and share how that might affect the classroom environment. Cite all sources used in your response.
2.  Select one childhood development stage. Based on brain development, what behaviors and challenges are expected at this stage? Link these to the specific parts of the brain that are developing or not developed at the selected stage.