Tracy Jennings, Works at Noodle and here to help!
According to the Bucks County Montessori Charter School website, its students come from Bristol, Bensalem, Centennial, Council Rock, Morrisville, and Neshaminy in addition to the its host district, Pennsbury. In short, anywhere in Lower Bucks County. It doesn't seem that any districts closer to Trenton send students to this school, but I recommend calling the front office to confirm (215-428-6700).
Noodle has additional help for you in determining where to send your child for school. There is a school search function and many articles about school choice and finding the right school for your child.