The "Student Visa Security Improvement Act" aims to enhance the security and oversight of foreign students and exchange visitors in the United States. It requires the Secretary of Homeland Security to strengthen student visa background checks within 180 days, mandating regulations for employees to review all F, J, and M visa applications, conduct in-person interviews, and specifically assess for inadmissibility due to terrorist activities. Employees must also conduct on-site reviews of applications and update the memorandum of understanding with the Department of State to clarify roles. The bill significantly amends the Student and Exchange Visitor Program (SEVP) by requiring new regulations within one year. Institutions and sponsors must ensure students are active participants and are not unobserved for more than 30 days during an academic term or 60 days otherwise, with all status changes reported within 10 days. The Secretary is also mandated to require observation of each covered student or exchange visitor at least once every 60 days. To support these changes, the legislation mandates enhanced access to the Student and Exchange Visitor Information System (SEVIS) for institutional employees, requiring certified users and technical support. SEVIS must be upgraded to include data fields for academic performance verification and timely reporting, and the Secretary gains authority to decertify institutions or sponsors without notice for egregious criminal activities or national security threats. Finally, the bill directs the Comptroller General to review SEVP fees and requires biannual reports to Congress on student compliance and institutional reporting.