Episode 26 of "Sabrina, the teenage witch"
s02e02 Sabrina Gets Her License (2/2)

An hour-long second season opener finds Sabrina celebrating her 17th birthday - which means that besides presents, she gets her copy of the witches' handbook and instructions to study it for a forthcoming test. But she must also cope with her classwork (including extra algebra), her responsibilities to boyfriend Harvey (including baking cookies and making a poster of him for the school dance), her shy new friend Valerie, and Libby's plot to take over as editor of the school newspaper. Exhaustion causes her to fail her preliminary exam, and be sentenced to witch boot camp... and her aunts are not allowed to warn her about the more serious penalty if she fails a second time. Meanwhile, when Hilda and Zelda's 300-year-old bond matures, Zelda decides to switch from physics to chemistry and buy a top of the line "lab-top" chemical laboratory which naturally proves irresistible to Hilda, Salem and Sabrina... and Salem makes off with some of the cash to buy new cat toys and a meal at a sushi bar.