This Google Form is the registration page for the Global Project Based Learning (GPBL) 2021 program on Mathematics, a virtual short program organised jointly by Shibaura Institute of Technology in Japan and Institut Teknologi Sepuluh Nopember in Surabaya, Indonesia. According to the form description, the program offers young mathematicians, analysts and researchers a space to connect, network and sharpen problem-solving skills. It ran from 2 to 7 August 2021 over six days, with three-hour sessions each day from 13.00 to 16.00 WIB (15.00 to 18.00 JST) on Zoom. The form thanks participants for registering and lists contact details for two organisers, including an email address and WhatsApp numbers, for further questions. It is intended for students and early-career researchers interested in collaborative, project-based mathematics learning.