Research has found that there is a high risk of educational underachievement for children who are from low-income housing circumstances. This is often a process that begins in primary school for some less fortunate children. Instruction in the US educational system, as well as in most other countries, tends to be geared towards those students who come from more advantaged backgrounds. As a result, children in poverty are at a higher risk than advantaged children for retention in their grade, special deleterious placements during the school's hours and even not completing their high school education. Advantage breeds advantage. There are indeed many explanations for why students tend to drop out of school. One is the conditions of which they attend school. Schools in poverty-stricken areas have conditions that hinder children from learning in a safe environment. Researchers have developed a name for areas like this: an urban war zone is a poor, crime-laden district in which deteriorated, violent, even war-like conditions and underfunded, largely ineffective schools promote inferior academic performance, including irregular attendance and disruptive or non-compliant classroom behavior. Because of poverty, "Students from low-income families are 2.4 times more likely to drop out than middle-income kids, and over 10 times more likely than high-income peers to drop out"