In this video, students learn how to pronounce the short "ah" sound by understanding the concept of closed syllables. The teacher explains that in closed syllables, a vowel is followed by a consonant, resulting in a short "ah" sound. The video provides examples and encourages students to identify vowels and determine if they are part of closed syllables. By the end of the lesson, students will have a better understanding of when to use the short "ah" sound in words.