The best revision as a rebuttal to the counterclaim is:
Students usually study government and civics during the last two years of high school, so 16- and 17-year-olds find voting to be a way to engage with what they learn.
This response directly addresses the counterclaim by emphasizing that educating young people about government can lead to increased civic engagement, suggesting that lowering the voting age could help make them more active voters in the future.