The sentence superiority effect observed with skilled adult readers has been taken to reflect parallel processing of word identities and the rapid construction of a preliminary syntactic structure. Here we examined if such processing is already present in primary school children in Grade 3 (average age 8.9 years). Children saw sequences of four horizontally aligned words presented simultaneously for 500 ms and followed by a post-mask and post-cue indicating the position for report of one of the four words. Word identification was more accurate in grammatically correct sequences compared with ungrammatical scrambled sequences of the same words, and this sentence superiority effect did not interact with position. This replicates the pattern found in prior research with adults and suggests that parallel word processing and the associated efficiency in syntactic processing are already in place in Grade 3. We also found that accuracy in identifying words, independently of the surrounding context, correlated with reading age. This points to efficient word-in-sequence identification as one key ingredient of the process of becoming a skilled reader.