LittleLearner: Language Models Under Pedagogically-Controlled Knowledge Exposure

Modern LMs are trained on everything at once, so it is hard to tell whether a new skill was learned or merely elicited. We constrain the training distribution itself: an 88B-token corpus filtered to the U.S. elementary-school curriculum, with models trained from scratch on it and matched unfiltered controls. In our experiments, scaling, SFT+GRPO post-training, and in-context learning amplify what the curriculum taught, but none meaningfully improves out-of-scope performance, indicating that the pretraining filter sets the effective capability ceiling.