In the last two years, Denver union officials say, membership has swelled to 3,800. That means 72 percent of eligible teachers, nurses, counselors and others now belong to the union.
The talks on teacher pay began at 10 a.m. and are scheduled to last until 8 p.m.
That all but one Skinner teacher joined the strike stands out considering the school district said about 56 percent of Denver teachers did not show up Monday.
Denver Public Schools and the teachers union will restart negotiations at 10 a.m. Tuesday.
The strike will affect 71,000 students across 147 schools, and 5,353 teachers and specialized service providers.
Gov. Jared Polis is still encouraging teachers and Denver Public Schools to restart negotiations to avoid the strike.
When negotiations resumed last week, the wedge between the teacher's union and the district grew even larger.
Studies show children who attend full-day kindergarten go on to perform better, and that the program evens the playing ground for students who would otherwise be at a disadvantage.
The rejection of the school district’s latest offer comes after 14 months of contentious negotiations to overhaul the district’s pay and teacher incentive system.
The hearing was held in the capitol’s largest committee room and even then the crowd filled four overflow rooms.