K-12 Cybersecurity Act of 2019 This bill requires the Office of Cybersecurity and Infrastructure Security (OCIS) to study the cybersecurity risks facing K-12 educational institutions and develop recommendations that include cybersecurity guidelines designed to assist such institutions in facing those risks. The use of such recommendations shall be voluntary. The study shall include the challenges that such institutions face in securing (1) information systems owned, leased, or relied upon by those institutions; and (2) sensitive student and employee records. OCIS shall (1) develop an online training toolkit designed for officials at K-12 educational institutions to educate the officials about, and provide strategies to implement, the recommendations; and (2) make available on the Department of Homeland Security website the study's findings, the guidelines developed, and the toolkit.