(bright music) <v ->In this year three lesson</v> from the unit, "Introduction to Light and Shadows," pupils expand their substantive knowledge of light by learning that the sun emits different types of light, including ultraviolet, UV light, which can be harmful even though the sun is very far away. Prior to this lesson, pupils learned that sunglasses have special lenses that can protect our eyes from UV damage caused by the sun, and that different sunglasses provide varying levels of protection from UV light. Guided by the teacher, pupils discover that some scientists plan different types of inquiries to help them develop sunlight protective lenses for sunglasses. An example of a scientist's inquiry question could be, "Which sunglasses give the best protection for our eyes from the sun?" <v ->So Izzy here is saying,</v> "None of these sunglasses have UV stickers on them. Okay? So I wonder which pair is the best." Our question is today, which sunglasses give the best protection for our eyes from the sun? Izzy has got an idea for her ones. So she says, "I could wear each pair of sunglasses, look at the sun and decide which pair the sun looks the brightest to me." Do we think that's a good idea? <v Class>No. </v> <v ->Okay, so Alex says, "That would be very dangerous. </v> You must never look directly at the sun, even when wearing sunglasses." <v Melanie>This video shows pupils as active participants,</v> sharing their initial planning ideas on individual post-it notes and discussing how they might investigate safely without looking directly at the sun. <v ->You are going to write down our ideas</v> on your post-it notes of best way to investigate which sunglasses are best. We've got, "Use the moon to look at." And we've also got, "You could reflect a mirror or use a candle." <v ->Pupils explore how UV beads change from white</v> to dark colours when exposed to UV light. Following this, they have opportunities to revise their plans and suggest improvements to their investigation by comparing UV beads that have been placed under the lenses of different pairs of sunglasses and left in direct sunlight. <v ->What happened with the beads</v> when you shined the UV light? What happened, Freddy? <v ->They changed colours. </v> <v ->They changed colours and then did they go darker?</v> <v ->Yeah, they went darker. </v> They changed to purple, pink or, in fact, even blue. <v ->Okay. </v> <v ->Different torches. </v> <v Teacher>And then what happened</v> when we took the UV torch away? <v ->They started going paler and then they turned white. </v> <v ->By focusing this lesson on the planning stage</v> of the inquiry, pupils develop their understanding of how to compare different groups of beads in a fair way. They will change only one variable, the type of sunglasses. They will also consider how to keep all the other factors the same. In doing so, pupils develop their disciplinary knowledge of how to plan and set up a simple practical inquiry. <v ->Put the beads under the sunglasses one by one</v> and shine the UV torch over them, then see which beads are the least coloured. <v ->Tape a UV bead on sunglasses,</v> and get a UV torch and test them. If they are white, it's fine to wear. If it turns dark, it's not good to wear. <v ->Different groups of beads must be compared in a fair way. </v> Okay. This means that only one thing can be changed. The only thing that we are going to change is going to be the sunglasses. The beads are going to stay the same, but the different types of sunglasses are going to change. <v ->Once pupils have completed their plans,</v> they will use these to set up and carry out their inquiry to answer the question, "Which sunglasses give the best protection for our eyes from the sun?" (bright music).