Yup. About $15 for a 5’x5’ sheet of B.B., which is 3x5 full 12x20 pieces.
The new stuff I got is even cheaper (Meranti Lauan) at $12 or so for 4’x8’, but the quality isn’t as good.
Bonus:
https://community.glowforge.com/t/settings-for-1-8-meranti-lauan-plywood/21606