PURPOSES: to compare the performance of good and bad readers and writers of public and private schools in reading aloud and writing under dictation regarding the parameters of writing and reading fluency, besides to verify the reading and writing strategies used by these children. METHOD: 61 students of the 4th and 5th grade from a public (GPu) and a private (GPr) elementary school were submitted to a School Performance Test, for classification into good and bad reader and writer; and to reading aloud and writing words and pseudo words in order to verify their performance regarding the total number of successes in reading and writing, rate and accuracy in reading and accuracy in writing, as well as strategies for reading/writing used. RESULTS: in a general overview, the performance of participants from private school was higher than from public school. There was better performance in reading than in writing; in words than in pseudo words; in high frequency words than in low-frequency words; in regular words than in irregular words. The effects found in reading and writing were the same for public and private schools. CONCLUSION: social and pedagogical aspects influence the performance of reading and writing. In the group studied, it was observed the effects of lexicality, regularity and frequency; it was not showed the preferential use of one or another route of reading and writing. The type of school does not seem to interfere in the strategy of reading / writing used by these children.