HOUSTON -- Hundreds of students in the Houston area protested Tuesday for the second day in a row as the U.S. Senate considers proposed changes to the country's immigration laws.

Officials with the Fort Bend, Houston and Pasadena independent school districts said hundreds of students walked out of school between 8:30 a.m. and 10 a.m. Tuesday.

Many of them marched to the steps of Houston City Hall in downtown to protest House Bill 4437, which would make being an undocumented immigrant a felony.

Austin High School student Edgar Gonzalez, a child of Mexican immigrants, was one of two students who spoke with Houston Mayor Bill White about immigration reform.

"My parents are breaking their backs just to keep the food on the table," Gonzalez told KPRC Local 2.

District officials said students from Sam Houston, Davis, Furr, Milby, Chavez and the High School For Law Enforcement and Criminal Justice gathered to chant, wave flags, and speak out.

"We are trying to show that we care about people," student protestor Dario Duarte said.

HISD spokesman Terry Abbott said school buses were sent to City Hall to ensure the students were safely transported back to school. Abbott said the buses were not used to transport the protesting students to City Hall.

District officials met Tuesday afternoon to discuss what disciplinary actions the students could face for leaving campus.

HISD Superintendent Abelardo Saavedra released a statement that said all students who participated in the walkouts would be disciplined. Students could be placed in detention or in-school suspension, and may also be subject to other sanctions.

Officials said that each student's disciplinary record and the wishes of the student's parents would be taken into consideration on a case-by-case basis.

To read Saavedra's full statement, click here.

Before the walkout, teachers encouraged the students to write their legislators.

"We encourage our students to be involved in their community, to be aware of issues that affect society, to care about those types of things. But there is an appropriate time and place for those activities and abandoning your studies a week before TAKS testing is simply not the proper time and place," an HISD official said.

Houston City Councilwoman Carol Alvarado believes the students should not be punished.

"I'm proud of what they did, but we do want them to stay focused. They've got to go back to school and to be educated," Alvarado said.

FBISD officials said about 150 Hightower High School students and 30 Lake Olympia Middle School students who walked out of school Tuesday morning were followed by Fort Bend ISD and Missouri City police as they marched.

District spokeswoman Mary Ann Simpson said the students refused the district's offer to take them back to school. School officials planned to identify the students and contact their parents.

"Our priority is the safety of these students and other members of the community," Simpson said in a news release.

FBISD has not yet said what disciplinary action the protesting students could face.

In Pasadena, about 500 students walked out of Pasadena High School shortly before 10 a.m. School district officials told KPRC Local 2 that any student who left campus would be given an unexcused absence.

Pasadena police said there were 14 arrests for a variety of offenses, including curfew violations, disorderly conduct, resisting arrest and assault.

During the protest, a police car was surrounded and rocked by marchers, and spray-painted with green paint, police said.

Houston police also took some students into custody and cited several for daytime curfew violations.

About a thousand Dallas-area students participating in a walkout rushed Dallas City Hall before 11 a.m. Authorities said the students flooded the first two floors of Dallas's City Hall before police and security guards were able to usher them back out. No word on damage, injuries or arrests.

A girl's hand was severed when a vanload of Dallas students rolled over at an East Dallas intersection. Dallas Independent School District spokesman Donnie Claxton said the van contained students from Spruce High School and sped past Skyline High into an intersection, where it overturned. Authorities said an underage classmate was driving the van.

The girl was hospitalized with her injury. No word yet on whether others in the van were hurt.

Approved Measure Would Let Illegal Immigrants Apply For Citizenship

The Senate Judiciary Committee approved a measure Monday that would permit illegal immigrants currently in the country to apply for citizenship without first having to return home, a process that would take at least six years.

Senate Majority Leader Bill Frist said he hopes the Senate will pass an immigration reform bill by April 7. But any bill produced by the Senate would have to be reconciled with a House bill that would make illegal immigrants felons.

A get-tough version that passed the House would add more fencing along the U.S.-Mexico border and increase penalties for those who sneak across, but it did not include the guest worker program that Bush wants.

President George W. Bush is insisting that Congress send him a bill that not only strengthens U.S. borders, but also allows foreigners to have a guest permit that lets them work temporarily in the United States in low-paying jobs. "It's a humane way to deal with people who are making a contribution to our economy," he said.

There was no immediate White House reaction to specifics of the Senate panel version, but it was more in line with what Bush has proposed than was the House bill.

Congress already has failed to give Bush several other priorities that he asked for during his second term. Despite spending months last year pitching an overhaul of Social Security, lawmakers never even took up a bill for debate. And this year lawmakers turned back one of Bush's three nominees to the Supreme Court before Harriet Miers' name even came to a vote and made clear they would block the administration's plan to let a company based in the United Arab Emirates run some U.S. ports.