When the bell on top of the school's Leaping Tower keeps ringing, Sparks' Crew plans and conducts an investigation. They discover that vibrations make sound, but what's causing the bell to vibrate and ring? Curriculum: Vibrating matter can make sounds. / When Sparks' Crew decides to restyle their current hero suits, they have to figure out what materials they can use. But, is it the right stuff to help them save the day? Curriculum: Materials have different properties; it is possible to sort, describe and compare materials based on their properties.