This study explores Finnish children's word-level spelling by applying a linguistically based multilayered word structure model for assessing spelling performance. The model contributes to the analytical qualitative assessment approach in order to identify children's spelling performance for enhancing writing skills. The children (N = 105) participated in two dictation assessments at the end of their first and second grades. The results indicate that long consonants and consonant sequences are the most problematic structures in both the first and second grades. The less-advanced spellers were significantly weaker than others also in coding the overall syllable number, heavy unstressed syllables and long vowels in the first grade. In the second grade, they still had more difficulties in spelling heavy unstressed syllables and long quantities of vowels and consonants. The multilayered word structure model seems to give more information about the quality of spelling than error-based holistic analyses. The model is applicable for other shallow orthographies as well.