Schools that have called off a lot of classes because of last fall’s heat and last winter’s snow might not have to make up many of those days. Missouri schools are required to have 174 days of classes each school year. But bad weather sometimes forces cancellation of classes so many times that the school year would run well into June if all the lost time is to be made up. Legislation has been introduced in the State Senate to ease the requirement this year because of the high number of days lost to the weather. Supporters say one reason the special action needs to be taken is so teachers can finish their teaching in time to enroll in summer school, to take more education courses.