There are several ways for students to attend the Esri Education GIS conference (www.esri.com/educ) or the Esri International User Conference (Esri UC).
1. In the Fall prior the the conference, Esri accepts applications for the Student Assistantship Program - Please see Student Opps at Esri
2. The Education Discounted registration rate for UC is $495.
3. There is a special rate via the YPN program
I hope this helps.
Regards,
Ann Masangcay
Esri Education Outreach Program