Wannabe,
My children attended a Catholic School for one year. Not only did they allow earlier entrance into K they actually approached me after the first two weeks of first grade for DS to say they wanted to grade skip him to second! We moved and did not continue there but the public schools did honor his grade skip so for us the Catholic school was a great thing. There was no "second class" citizen feel to not being Catholic and the PTO was open and friendly to me as a parent as well.
Of course all schools are different regardless of affiliations etc. and perhaps you can find some other non-Lutheran parents to see what their experiences have been.
Good Luck!
Breakaway
