The Senate Education Committee chairman expects to have the third piece of public schools reforms ready for introduction by tomorrow.     Sen. John Goedde says the measure has undergone significant changes. For instance, a provision that would have eliminated 770 classroom teachers and boosted class sizes is gone, leaving decisions over how to allocate state funding - and how many teachers to retain - up to local school districts.      The requirement that students take online courses will be stricken, Goedde adds, with the Board of Education instead directed to draft rules governing policy on how the Internet will figure in the classroom in coming years.  And while the legislation still foresees ninth-graders eventually receiving laptops, teachers will be the first to get them starting in 2013, with training to use them.