Welcome to class, students. Please put on your drinking caps.

At upscale Lower East Side watering hole Copper & Oak, booze aficionados are sipping their way to deeper knowledge in a happy-hour lecture series all about liquor. For anyone who’s wondered how climate affects Taiwanese whiskey grains, or who wants to grasp the true smoky pedigree of mezcal, Copper & Oak’s Spirit School is the spot to be.

Introduced in June, the bimonthly classes are led by owner Flavien Desoblin (also owner of Brandy Library in Tribeca), spirit sommelier Joel Cuellar and others from Copper & Oak’s roster of drink pros.

Some classes delve deep into single spirit categories, such as brandy. Others pit two types against each other — think bourbon versus rye. An “Alt Whisk(e)y” series showcases trends and upstart producers of the namesake liquor. And, yes, each class includes four 1-ounce shots of the subject matter.

The atmosphere is scholarly, without the brand sponsorship seen at many traditional tastings.

“It’s really [about] explaining the juice in the glass,” Desoblin says. That’s because Copper & Oak’s clientele — especially the younger set — is sincere in seeking a boozy education. “Millennials can see through the brand speeches.”

Classes meet twice monthly on Tuesdays, from 5 to 6 p.m. A $50 fee covers the tasting tab. (Skip the samples for a reduced fee of $10.)

Of course, if a self-paced lesson is more your style, stop by and belly up to the bar, where a helpful pro can always offer guidance.

Here’s to higher learning.

Copper & Oak, 157 Allen St.; 212-460-5546