If passed, the state would give $9 billion in general obligation bonds
(i.e. debts paid back with interest, paid by tax-payers) for school construction projects. $7B for K-12 public schools. $2B for community colleges. Lots of details
The debate is not about whether schools should get money. Many schools are in disrepair and there hasn't been a bond approved since 2006.
Opponents, including Gov. Jerry Brown, oppose the prop because it adds $500M of debt every year to the budget, it seems to bank roll construction companies, and it won't go to the neediest school districts.
He says the legislature can make a better proposal. Supporters point out that schools really need it right now. Opponents counter that school population is declining, and this is not the most urgent thing on the budget.
The state legislature tried to put a similar act on the ballot in 2014, but Gov. Jerry Brown opposed it. This proposition was created by a group made up of school districts and construction groups to bypass the state government and get money to school construction projects in need.