I wouldn't be hesitant about applying your assumptions about progressives in general to progressives on Less Wrong.

, in particular a lot of libertarians would argue that government should get out of the business of setting school curricula entirely.

That doesn't mean they can't also have opinions about what should be in a science curriculum given that local governments legislate such things as a matter of fact. If groups are going to refuse to join in any political action that is inconsistent with their idealized world than probably no cooperation is possible at all. The whole point is to find narrow issues of reform where there can be temporary alliances. You can oppose the teaching of intelligent design in public schools while also wanting voucherized education and a you can favor eliminating the mortgage tax deduction while also wanting a social welfare state that ensures everyone has housing.