Correction: An earlier version of this article misstated the political party of Del. Herbert H. McMillan of Anne Arundel County. He is a Republican, not a Democrat. This version has been corrected.

Maryland is on the verge of raising the age that children would be required to stay in school, following a national trend intended to help more students become ready for college and careers.

Both chambers of the General Assembly have approved bills that would generally require students to turn 18 before they can drop out of school. The current minimum dropout age is 16.

On Thursday, the House of Delegates passed its version, 88 to 49, after an impassioned debate. A final bill is expected to be sent to Gov. Martin O’Malley (D) before the legislature’s planned adjournment on Monday.

Maryland is poised to join 21 other states, including Virginia, and the District in having a dropout age of 18, according to Sunny Deye, a senior policy analyst for the National Conference of State Legislatures. Eleven states have set the age at 17; the rest, 16.

In his State of the Union speech in January, President Barack Obama urged state legislatures to increase the dropout age to 18. That raised public awareness of the issue, some state education lobbyists said, and state legislators in Maryland cited Obama when they urged colleagues to support the bills.

Proponents argue that the legislation would help students in lower-income families and help the state save money on social services. “We have a moral obligation to educate all kids in this state,” said Del. Anne R. Kaiser (D-Montgomery), a chief proponent of the House bill.

But opponents say that parents are ultimately responsible for their children’s schooling and questioned whether the bill would significantly increase the number of children who attend school.

Both the House and Senate versions would increase the dropout age initially to 17 and ultimately to 18.

National education experts say that this makes the legislation highly unusual. Often, states implement the change in a single step. The experts say the schedule allows Maryland more flexibility with implementation and can make the bill more palatable to state legislators.

State legislative staff members estimate that, with more students staying in school, the state will spend an additional $35 million in local education aid when the dropout age is raised to 17. Once it rises to 18, the cost will be about $54 million more a year, according to the estimate.

“It means more money,” said Del. Herbert H. McMillan (R-Anne Arundel), who opposed his chamber’s bill and predicted that many students subject to the new requirement would cut class. “It doesn’t mean the kids are in school.”

The bill exempts several categories of students from the new requirement, including those who are home-schooled, those who must work to provide financial assistance for their family and those who are pregnant.

About 9,500 students have dropped out of Maryland schools each year, according to legislative staff members. The problem is particularly acute in Prince George’s County, which has the highest dropout rate in the state.

Gene Streagle, executive director of the Maryland Association of Secondary School Principals, said principals can tolerate the bill. But he added that the state should be improving dropout rates in other ways, such as tweaking statistics to count students who graduate high school in six years.

Deye said the legislation is a helpful tool. “It’s symbolically important for state laws to indicate that kids shouldn’t be leaving school before they receive a high school diploma,” she said. “It’s no longer a viable option to drop out.”