What is considered a major focus of the psychological practice that emerged between 1870-1909?

The major focus of psychological practice that emerged between 1870 and 1909 primarily revolved around the development and use of empirically valid psychological tests. This period marked significant advancements in the scientific foundations of psychology, as practitioners sought to establish the discipline as a credible science through the standardization and measurement of mental processes, abilities, and personality traits. One of the notable figures during this time was Alfred Binet, whose work led to the development of intelligence testing, which became a cornerstone for educational assessment.

The emphasis on valid psychological tests also paved the way for integrating psychological principles into educational settings, ultimately influencing school practices. Testing during this era provided a framework for measuring cognitive abilities and helped identify students' needs, informing interventions and educational strategies. This emphasis on empirical data established a methodological approach in psychology that continues to be relevant in various subfields, including school psychology.

While other developments such as special education laws and professional growth in training are indeed important, they are more reflective of the aftermath of the groundwork laid during this era rather than the primary focus of the practice itself at that time. The expansion of school psychology was a natural progression resulting from the advancements in empirical testing, solidifying the foundation for the profession as it moved forward.