The bill's sponsor, Rep. Ed Robb, R-Columbia, said mothers of multiples came to him with concerns over how and why their children are placed in certain classes.
"They said, 'In some places, principals and superintendents are making decisions we think we should make,'" Robb said.
Tanya Alberty, president of the Columbia Mothers of Multiples Club, said she had asked Robb to speak about the issue at a club meeting. Robb later offered to sponsor the bill, she said.
Alberty, a mother of triplets in preschool, said she has not had any trouble with Columbia schools. She said she heard about the legislation, a form of which was first introduced in 2006, from unhappy parents in the St. Louis branch of the club.
Alberty said parents there told her that St. Louis schools are strict about not allowing multiples to be together in the same classroom. The Board of Education for St. Louis schools does not have any written policy for assigning multiple-birth siblings to specific classrooms, according to its Web site.
Both Alberty and Robb said some school districts justify their decisions by citing research on multiples' behavior.
"You can't say as a generalization all multiples should be separated," Alberty said.
But Brent Ghan, spokesman for the Missouri School Boards Association, said those policies are based on the fact that school boards know students' needs.
"Local school boards are in the best position to make decisions based on the needs of the local community," Ghan said. "That is why we don't have one school board."
Ghan said MSBA thinks classroom placement should be a local policy decision.
"This is not a one-size-fits-all situation," he said.
However, Robb said he thinks parents should have the last word.
"The most local you can get is the parents," he said.
Alberty said she hopes the bill will eliminate a lot of frustration for parents of multiples.
"Frankly, of all the people I've talked to, no one has had a problem with (this bill in Columbia)," she said. "I don't want to be so upset about it that I go another route away from public schools."
The bill would require that parents who want their children in the same classroom to make the request within 14 days after the first day of school or the date of the children's enrollment.
Similar legislation was first introduced in the House by Rep. Sam Page, D-St. Louis County, in 2006. That bill wasn't assigned to a committee until the last day of the legislative session -- when it was too late for the committee to do anything with it.