Lagos is home to 12,098 private schools catering to 57% of the state's enrolled children, from ultra-rich to relatively poor households, with many schools targeting those of lower socio-economic status. Government schools were intended to provide a just and equitable option for all; however, they have not kept pace with demand in terms of both capacity and quality, causing concerned parents to look elsewhere. This paper draws on original household survey data to investigate why parents living in slums would put considerable strain on their household budgets to access fee-paying primary education for their children, and discusses the equity implications of this situation. Context is provided through data from the first comprehensive private school census in Lagos during the school year 2010-2011. It is found that parents choose private schools because government schools are perceived to be failing (or too far from home), but also that they have higher expectations than can be provided by private schools run on incredibly tight budgets with often untrained teachers. It is highly questionable then how under such circumstances social justice can be served through this scenario.