Highlights • We test the power of children's learning during independent reading. • Young readers learn spellings and meanings of words in their independent reading. • Children's skill in learning orthographic forms is related to word reading. • Children's skill in learning word meanings is related to reading comprehension. • Findings support the inclusion of learning capacity in theories of reading. Abstract Independent reading offers children opportunities to learn the spellings and meanings of words. Evidence to date shows that older children take advantage of these orthographic and semantic learning opportunities. We provided a much-needed test of whether young readers can acquire spellings and meanings of novel words through independent reading as well as of whether each of these skills explains individual differences in word reading and reading comprehension. To test theory stringently, we assessed whether these effects are separable from those of decoding. A sample of 66 English-speaking children in Grades 1 and 2 independently read stories containing novel words referring to new inventions (e.g., a veap used to clean fish tanks). We scored accuracy in reading the novel words in the stories to assess target decoding. Children completed choice measures evaluating their learning of the novel words' spellings and meanings along with word reading and reading comprehension and controls for age, short-term memory, vocabulary, and phonological awareness. Scores for both the orthographic and semantic learning measures were higher with successful decoding than without it. At both grade levels, children were above chance in choosing correct spellings and meanings even when they had not accurately decoded the target a single time. In terms of individual differences, after accounting for controls including target decoding, orthographic learning was related to word reading and semantic learning was related to reading comprehension. Young children have powerful skill in learning spellings and meanings through their independent reading, with highly specific impacts of such learning on reading outcomes. [ABSTRACT FROM AUTHOR]