This study examined first grade children's spelling of vowel sounds in relationship to the spellings these children were taught in their reading series and to the phonological aspects of the sounds. The subjects for the study were 12 first graders, six boys and six girls, in a public school in a Boston suburb. Written work done in school was collected; at least 300 words were written by each child. The spelling of each vowel sound in every word was tabulated, with separate tabulations made for words spelled conventionally (correctly) and for words spelled unconventionally (incorrectly). With few exceptions, the children spelled whole words conventionally only if the words were common words. The children spelled certain vowel sounds as the sounds are spelled in common words. Even though the children repeatedly practiced filling in missing vowels, they did not carry these spellings over into their own writing. The children also represented phonological features of the sounds in their writing. Encouraging young children's spelling in the classroom is discussed, with reference to the kinds of activities that were used in this study and the teacher's attitude toward spelling. (Author/TS)