Trouble is, the child I started the game with is too old for mushrooms and I suspect that breeding another child (even if I can, while the villagers are worried about food) will consume more food than I will gain in mushrooms.

10K tech points to go until fishing... I went for level 2 in science hoping that the increased rate of aquiring tech points would make up for the cost of getting level 2. At the moment I'm not sure that calculation was right - will have to wait and see.