By the end of 1st grade, how many root words is the average child expected to know?

By the end of 1st grade, the average child is expected to know around 5,160 root words, making this the correct choice. This expectation aligns with literacy development standards that emphasize vocabulary growth as children learn to read and write. In 1st grade, students engage with words in various contexts, allowing them to build a foundational vocabulary that supports their understanding of language.

The focus in early education is on not just recognizing and using words but also grasping the meanings and nuances associated with these root words. This vocabulary development is crucial as it enhances reading comprehension and communication skills, laying a solid groundwork for future academic success. Additionally, children begin to understand patterns in language, enabling them to further expand their vocabulary as they advance in grade levels. Hence, the target of approximately 5,160 root words reflects the growth in linguistic competence expected at this stage of education.