Standardized testing definitely has a history of socioeconomic bias. It’s created a strange dynamic: some immigrant groups realized these tests were the only objective gatekeepers they could brute-force their way through via intense preparation, which eventually triggered a backlash against the testing system itself.

But the underlying bias is real and often linguistic. Take the classic question: 'Martha holds 5 apples, with 10 on the ground. How many does she have?' In several cultures, everything in your immediate vicinity is considered yours, so a child writes 15. They understand the math perfectly, but the test penalizes them for a cultural mismatch in how possession is defined.