From the description:

Own the short: https://www.rifftrax.com/masks-of-grass

Is corn masks? The freaks at ACI Films return yet again with a twisted spin-off of the classic At Your Fingertips short.

The parents have signed the waivers and headed to a bar, leaving their unfortunate kids to assemble “masks” out of various types of refuse. They’re potentially problematic, and definitely swarming with pests. One thing is for certain: nobody learned a damn thing the day this was shown in class. But it may have inspired a cult or two! Join Mike, Kevin, and Bill for Masks of Grass.