This paper provides evidence on how a low-cost, online, and scalable financial education program influences older participants’ financial knowledge. We tested the program using a field experiment that included short stories covering three fundamental financial education topics: compound interest, risk diversification, and inflation. Two surveys were administered eight months apart to measure the effects of those stories on participants' short-term and longer-term knowledge and financial distress indicators. We show that the risk diversification story was the most effective at improving participants' knowledge, in both the short and longer term. The compound interest and inflation stories significantly increased participants' knowledge in the short term, but the gain in financial literacy declined over time.