With teachers and college students taking to the streets to protest budget cuts on Thursday,  Democrats in the Legislature took a step toward restoring $900 million of the more than $2 billion that Gov. Schwarzenegger has proposed to cut from K-12 schools and community colleges.

They did so, largely along party lines, in passing a variation of the “gas-tax swap” that Schwarzenegger proposed. That’s the sneaky plan to eliminate the 6 percent sales tax on gasoline and replace it with a 17.3 cent excise tax on gasoline. Doing this will free more than $1 billion for the general fund, because  there were tighter restrictions on the use of the sales tax revenue.

Eliminating the sales tax on gas also would lower the state’s minimum requirement under Proposition 98 – the primary source of revenue for K-12 schools and community colleges – by $900 million. By lowering the obligation, the governor could still claim that he was fully funding Prop 98 – as if  districts wouldn’t notice the difference.

The Democrats’ version would hold the schools harmless by raising the percentage of the general fund that must go toward K-14 schools. Instead of a minimum of 40 percent, it would be slightly higher under Prop 98’s Test 1 formula. (Don’t ask me to explain why Test 1 this year.)

Schwarzenegger hasn’t said whether he would sign the bill. Democrats would have to find some other cuts or revenue to make up for the $900 million – which, come June, will be easier said than done. But at least they have make clear that education will be the priority.