The Magic School Bus - Season 3 Episode 10 -

When Phoebe tries to grow a big vine for her school's production of Jack and the Beanstalk, all she ends up with is a stunted little sprout. To help out, Ms. Frizzle turns her into a real vine. But to grow tall, Phoebe needs to figure out how plants eat - fast! To unearth the amazing ways plants make their own food, the Friz and the kids shrink down and dig deep in a quest to root out the facts!