This dissertation contributes to a growing body of research on the microeconomics of development in Sub-Saharan Africa. Fertility, labor market participation and agriculture are key components of the microeconomic development process in Tanzania. I explore household and individual decisions in all three of these domains in Tanzania through economic analysis and impact evaluation. Both experimental and non-experimental impact evaluations improve the public understanding of what works in economic development. For the first essay in Chapter 2, I explore household fertility decisions by estimating the effect of a community family planning education program on fertility behavior in the Meatu District. In Chapter 3, I investigate the effects of an entrepreneurship training program on financial literacy and employment attitudes in the Kagera region. In Chapter 4, I analyze the impact of polygyny on agricultural productivity in farming households across the country.