Common Core Standards
Grade 4
Reading RF.4.3.A
Use combined knowledge of all letter-sound correspondences, syllabication patterns, and morphology (e.g., roots and affixes) to read accurately unfamiliar multisyllabic words in context and out of context.
This substandard will serve students well through middle school, into high school, and straight through doctoral level work (folks really like difficult words at that level). If you can get students teasing out the nuances in sounds, patterns, and how roots and affixes work together, then you'll be getting them that much closer to being really great readers.