Michael Schoch, Answers questions on Noodle
Unfortunately, I have no first-hand experience with the school; however, I can point you towards these reviews. It looks like the school is very well regarded by parents and has a high rating from the state of Indiana.
Because it is a private school, it's not required to provide accountability or testing data. To learn more about the school's performance, I recommend calling and speaking with a member of the faculty or administration. You can reach the school at (219) 932-2686.
Since you asked generally about the state of the St. Casimir, I will include this local news report regarding a behavioral incident involving one of the pastors. I include it not to fog your perception of the school's academics, but because it appears to be a recent event, and one that was important to parents.
Here is a list of other private schools in the area, not all of them within Hammond.
Sorry I couldn't offer more information. Feel free to write back with any other questions you may have!