There are a few “sing-along” hymns in 3GRD-4GRD Latin. I have them on a youtube list here, including a sung version of the Pater Noster that we like.
An alternative site is THIS ONE. He recites the Our Father in English first, so you need to skip ahead to :45, if you just want the Latin. He does the same for the Gloria Patri, but his Table Blessing is at just in Latin and at a nice, slow speed.
I also have the lyrics and prayers in my Memory Book post here.