Municipal Court Judge Dan McNeary dismissed two of the cases June 8 and three others on Thursday, Round Rock City Attorney Steve Sheets said. Prosecutors had asked the judge to drop the charges.
Sheets said cases are still pending against 93 other students who have pleaded not guilty. Eighty-three others pleaded guilty or no contest and accepted either $200 fines or up to 32 hours of community service.
The students fighting the charges argue that the city's curfew ordinance includes exemptions for free speech and free assembly.
Round Rock's youth curfew ordinance requires students younger than 17 to be in school between 9 a.m. and 2:30 p.m. The students were cited March 31 when they walked out of class to join the daytime immigration rallies.
The Round Rock youths were among thousands of students in California, Texas, Nevada and other states that marched to protest tough immigration bills under debate in Congress.