This study examines whether youth's goals for their future societal engagement affect their future political activities. We hypothesized, first, that youth's political interest would be a central predictor of their future political activities and, second, that their goals for future societal engagement would moderate their political interest. The greatest future political activity would be among youth who were both politically interested and had set high goals. A community sample of about 400 16-year-olds (M[subscript age]=16.62, SD=0.71, 50.8% females) was followed over four years. The theory of planned behavior was applied. Different types of political action were predicted: offline political activities, online political activities, membership of a political/civic organization, and taking a stance in public for a party pre and post voting in a national election. Age-16 political interest significantly predicted all age-20 political activities, except for being a member of political/civic organizations and actual voting. In line with the second hypothesis, significant interactions were found between political interest and setting societal goals for all the future political activities except voting. It was concluded that youth's early-developed agency in setting goals for their societal engagement has widespread predictive utility for their political activities over a lengthy period.