What carrier are you looking at?
My family of 5 uses Total Wireless which runs on the Verizon network.
We pay $135 a month for our service (4 of us are on the $100/mo plan and share (evenly) 25GB of data, and my dd is on the singe line $35 plan, it is normally 5GB but there was a promo when she signed up so she gets 7.5GB).
I stock up when Target has Buy 1 get 1 20% off refills so sometimes the 4 of us are only paying $80 a month and my dd under $30.
There are alot of affordable options if you are willing to go to an MVNO, you just need to use one that gets good service in your area.