Pearl and her trusty rust-proof robot, Pascal, need to build a sandcastle before summer vacation is over, and they're going to do it using code. Pearl breaks the big we-need-a-sandcastle problem into smaller steps, then uses sequences, loops, and other basic coding concepts to tell Pascal exactly what to do. There are a lot of humorous mishaps along the way, but just when it looks like the sandcastle might never get built, Pearl uses her coding skills to save the day and create something even better: a gorgeous sandcastle kingdom!