First-year students at a high school in central China’s Hubei province were given a peculiar assignment prior to Monday’s online shopping bonanza: use their math skills to build models that could help their mothers save more money.

The students at Wisco No. 3 High School in Wuhan were asked to use various mathematical modules — tree diagrams, tabular methods, and abstract formulas — to finish the “Singles’ Day Shopping Advice for Mom” part of their assignment, Wuhan Evening News reported. Students quoted in the article said they helped their mothers save on a range of products including chocolates, dresses, handbags, and scarves.

Singles’ Day, which was started by tech giant Alibaba on Nov. 11, 2009, has turned into the world’s biggest shopping extravaganza, breaking sales records and spurring consumers to grapple with ways to find new discounts annually. This year, Chinese consumers spent over 10 billion yuan ($1.43 billion) in just the first 96 seconds after the deals went live at midnight. (Image: VCG)