The state with the lowest mid-year exam scores in the United States is typically Mississippi. This ranking is based on various educational assessments and standardized tests conducted throughout the year. According to the National Assessment of Educational Progress (NAEP), Mississippi consistently ranks among the bottom states in reading and mathematics scores. The reasons for these low scores are multifaceted, including economic challenges, educational resources, and systemic issues within the state's educational system.

Mississippi's economy has traditionally been reliant on industries such as agriculture and manufacturing, which have struggled to provide stable employment opportunities. This economic instability often correlates with lower educational attainment, as families may struggle to afford the resources necessary for their children's education. Additionally, the state's per capita income is significantly lower than the national average, which can limit access to educational resources and extracurricular activities that can support academic performance.

The distribution of educational resources in Mississippi also plays a crucial role in the state's low exam scores. Funding for public schools is often inadequate, leading to overcrowded classrooms, outdated textbooks, and a lack of technology. Furthermore, the state's teacher-to-student ratio is higher than the national average, which can hinder the ability of teachers to provide individualized attention to students who may need additional support.

Systemic issues within the state's educational system contribute to the low exam scores as well. For instance, there is a significant achievement gap between white and minority students, which is often attributed to disparities in funding and resources. Additionally, the state has a higher percentage of students who are English language learners and students with disabilities, which can further complicate the educational process.

Data from the NAEP, which is considered the gold standard for assessing student achievement in the United States, consistently places Mississippi at the bottom of the list for reading and mathematics scores. In the 2019 NAEP fourth-grade reading assessment, Mississippi ranked 50th out of 51 states and the District of Columbia, with only the District of Columbia scoring lower. Similarly, in the eighth-grade reading assessment, Mississippi ranked 50th.

In conclusion, Mississippi's low mid-year exam scores can be attributed to a combination of economic challenges, limited educational resources, and systemic issues within the state's educational system. Addressing these issues will require a comprehensive approach that includes increased funding, targeted support for at-risk students, and systemic reforms to improve the quality of education in the state.