(bright music) <v ->In this year five lesson, from the unit,</v> forces including simple machines, pupils expand their substantive knowledge of forces by learning that air resistance is a type of frictional force that acts between the air and the surface of a moving object. Through a range of experiences, pupils learn that air resistance affects how easily objects move through the air. Guided by the teacher, pupils focus on how parachutes rely on air resistance against the canopy to slow down a falling person. This video shows pupils as active participants, working scientifically and purposefully to develop and share their own questions about air resistance before devising more specific questions about parachutes and air resistance. In doing so, they develop their disciplinary knowledge by exploring their ideas and raising different questions. <v ->I want you to think about what questions you have</v> about air resistance, okay? So I'd like you to write these questions on your whiteboard. (pupils chatter) <v ->After three, show me your whiteboard, one, two, three. </v> Oh, interesting question. How's air resistance discovered? How long would it take for a parachute to hit the ground at six foot? Interesting. <v ->What would happen if you dropped a parachute with force?</v> Would the air resistance still make it go slower? <v ->There's some really interesting questions here. </v> And actually, some of these are I would quite like to have the answer too. <v ->Once pupils have devised their questions about parachutes</v> and air resistance, they should review the range of questions generated and sort them according to which can be investigated in the primary classroom. This provides an excellent opportunity for pupils to discuss which questions may lead to a comparative, or fair test investigation. <v ->My question is, how long will it take</v> for the parachute to hit the ground? (bright music continues) <v ->How many seconds will the parachute take</v> to hit the ground if there was no air resistance? <v ->Does air resistance always push or can it pull as well?</v> Will the parachute go faster when something is attached to it? <v ->Does a parachute work worse the higher you go?</v> (upbeat music).