Answer:
Longitudinal
Step-by-step explanation:
Longitudinal studies are conducted when the effect of the same variable influencing a subject takes place for a longer duration of time
Here, poverty of the children is the variable which they are being subjected to over a long period of time. Now, Dr. Casey wants to study the affect of poverty on a child's academic performance over a long span of time.
Hence, this type of study is called Longitudinal study