Recent studies [10, 23] using US nationwide databases showed high school boys spent significantly less time doing homework than girls, based on their responses to questionnaires and surveys. To investigate gender differences in homework in middle school, in this paper, we analyzed computer log data and standardized test scores of more than 1,000 7th grade students who participated in a large-scale randomized controlled online homework efficacy study. Students used the ASSISTments platform to do their homework for a school year. Our results suggested no significant difference between the time the two genders spent on homework overall. There was a marginally significant difference on homework time between genders in the high performing group only. When examining the system-student interaction data, we found significant difference between boys and girls in their help seeking behaviors. In addition, we found out that boys have benefited from the online homework intervention more than girls. [This paper was published in: Proceedings of the 9th International Conference on Educational Data Mining, June 29-July 2, 2016, Raleigh, NC. p364-369.]