Neat. Some of us in the r/toycameras community use 'Blue4est' which is a thermal paper filled with microscopic bubbles that collapse when exposed to heat as opposed to the endocrine disrupting BPA receipt paper. Another benefit of this paper is that the images can last for about 35 years. Toy cameras are a great gift for kids, and it can be neat for them to look back on the pictures they took from their little perspectives after they have grown up.

https://thermalprintcameras.wordpress.com/blue4est-paper/

More info on the current BPA problem in thermal paper: https://pmc.ncbi.nlm.nih.gov/articles/PMC3261950/