(Reuters) - Kansas Governor Sam Brownback on Thursday signed into law a school funding bill that will face scrutiny by the state supreme court to determine if it fulfills a mandate for adequacy. The Republican governor said he approved the measure even though the legislature “missed an opportunity to substantially improve the K-12 funding system.” The Republican-controlled legislature faced a June 30 deadline set by the Kansas Supreme Court in March to come up with enough funding to meet the state constitution’s requirement for adequacy. Alan Rupe, an attorney for school districts that filed a funding lawsuit, said the additional $293 million lawmakers allocated to schools over the next two fiscal years falls far short of what is needed. “We’re grateful for the effort, but it’s not enough to achieve constitutionality,” he said, noting that the Kansas State Board of Education had proposed an $893 million, two-year funding increase. Now that the bill has become law, Rupe said he expects the supreme court to set up a process for the state to demonstrate how the measure complies with the constitutional requirement.  Besides finding more money for schools, Kansas lawmakers also had to plug budget holes largely caused by falling tax revenue. Earlier this month, the legislature overrode Brownback’s veto of a bill hiking income tax rates to raise $1.2 billion over the next two fiscal years. 