Summa Theologica - by St. Thomas Aquinas


The greatest teacher of the Catholic faith Saint Thomas Aquinas, if you want a great catholic education, this is the way to go,
although for those who do not have the time to tackle this very lengthy book, or for those who have a hard time understanding it, there is also the "Shorter Summa" which is also by Saint Thomas Aquinas, which he wrote after his assistant, Brother Reginald, asked him to write a simple summary of the faith of the catholic church for those who lacked the time or the stamina to tackle his massive Summa Theologica.

which you can buy here(sorry it is not free online as for as i know) -
http://www.fraternitypublications.com/aqshsu.html

of course God is the best means of obtaining knowledge and wisdom, by prayer and contemplation, so lets make sure, no matter what we read, that this is the first means of obtaining a good catholic education.

Here is a prayer you may pray before studying or reading, write it down and keep it somewhere you will remember to use it -

Grant me grace, O merciful God, to desire ardently all that is pleasing to Thee, to examine it prudently, to acknowledge it truthfully, and to accomplish it perfectly, for the praise and glory of Thy name. Amen

(Indulgence of 300 days, each time. - Leo XIII. June 21, 1879.)