TNC, it doesn't sound like the current school is a good fit for your family. All Montessori schools can be quite different form each other but one of the reasons why we eventually chose not to send DD to a Montessori school is language art curriculum. My DD3.5 is a reader and has been for awhile. I wanted her to have a literature- and art-based reading and writing curriculum appropriate to her developmental needs and it wasn't going to happen at a Montessori school or really, at any school. At home, she has my attention one-one-one all day and I often spend however long it takes to find the next set of books for her to read that would build on her current skills and knowledge. No teacher is going to have that kind of time for each and every student in her/his classroom.
We're homeschooling for now and when she starts play-based preschool next year, I am going to pick her up right after lunch to avoid nap time so I plan to continue partial homeschooling with her. I thought of doing Montessori math at home as well and we might order some of their materials and have other manipulative available for her to explore but we'll probably settle into a combination of RighStart math and Singapore math when she is older but our main focus right now is creativity, open-ended play, and art/music education. We have outsourced dance and music to professionals but we have so much fun together at home. It doesn't feel like homeschooling, more like spending time together and enjoying things that we both love.
What I find overwhelming is keeping up with her interest in science. I am not a science person at all so while DD is an only child, I can relate to feeling at lost. If you do decide to homeschool, hiring someone to come sounds like a good idea but your little one might be ready to participate to some extent too. DD tried out a homeschooling coop once when she was 2 and she was fine for 3 hours working semi-independently because the group had the set up for children to work at stations, much like a Montessori school.
