They are the religious order involved in the education system in the Philippines. They were interested in teaching the Filipino children to read and to write. There is now a school now where this was first done called University of Santo Tomas.
This is known to be one of the best schools in the country. They do not just allow anyone to enter the school. There are only a chosen few who are allowed to enter and they have to abide by the rules stated by the school. The school still has very strong Catholic roots and have rules that are considered to be a bit conservative in modern times.