We first note that hand-wringing about the decline in US college enrollments has mistakenly linked such declines to the price of four-year colleges.

But the decline is entirely driven by two-year community colleges (and by for-profit colleges). The four-year sector is the dog that didn't bark.

Here is a comparison for the world population.un.org/wup/countryp...

3/5 Using matched student–teacher data from North Carolina plus high-resolution weather data, I find each additional extreme heat day lowers test scores in classrooms taught by the teachers aged 54 and over. For younger teachers, I do not find an effect.

Time is up for 1.5°C. The remaining carbon budget for 1.5°C is virtually exhausted: 170 GtCO2, equivalent to 4 years at the 2025 emissions levels.