01
![U5L1_Engage.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltf2ec83eee96ccb21/627b88c3fbd1dd35f419e84d/U5L1_Engage.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Maria notices that when she opens the window, her papers blow around the room.
How does that happen?
02
![Explore_Maria.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blt163d17de79c91d46/62710f096ed4423afc98da79/Explore_Maria.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
What is air?
How do you know whether it’s just empty space? Give some evidence from everyday life?
03
![45345_Science_U5_L1_Overlay.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blta0904d276c037ec7/628e0e79e2c49854288822a3/45345_Science_U5_L1_Overlay.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Build a fan that can make a breeze to blow over a paper tower.
04
Program your fan to make a breeze, starting with the speed set to 100%.
05
![45345_Science_U5_L1_Paper_1.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltc2971449043b24da/628e0e79bde8395bd0124e20/45345_Science_U5_L1_Paper_1.png?locale=en-gb&auto=webp&format=jpeg&width=216&height=124&quality=90&fit=bounds)
![45345_Science_U5_L1_Paper_1.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltc2971449043b24da/628e0e79bde8395bd0124e20/45345_Science_U5_L1_Paper_1.png?locale=en-gb&auto=webp&format=jpeg&width=216&height=124&quality=90&fit=bounds)
![45345_Science_U5_L1_Paper_2.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blta2b70aabc99d0d42/628e0e79af7b396927eddbaf/45345_Science_U5_L1_Paper_2.png?locale=en-gb&auto=webp&format=jpeg&width=216&height=124&quality=90&fit=bounds)
Use your model to try to blow over the paper tower.
06
![45345_Science_U5_L1_Paper_1.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltc2971449043b24da/628e0e79bde8395bd0124e20/45345_Science_U5_L1_Paper_1.png?locale=en-gb&auto=webp&format=jpeg&width=216&height=124&quality=90&fit=bounds)
![45345_Science_U5_L1_Paper_1.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltc2971449043b24da/628e0e79bde8395bd0124e20/45345_Science_U5_L1_Paper_1.png?locale=en-gb&auto=webp&format=jpeg&width=216&height=124&quality=90&fit=bounds)
![45345_Science_U5_L1_Paper_2.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blta2b70aabc99d0d42/628e0e79af7b396927eddbaf/45345_Science_U5_L1_Paper_2.png?locale=en-gb&auto=webp&format=jpeg&width=216&height=124&quality=90&fit=bounds)
Try different positions for the paper tower, like in front of the fan, on one side of it and closer or farther away.
07
![45345_Science_U5_L1_Paper_1.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltc2971449043b24da/628e0e79bde8395bd0124e20/45345_Science_U5_L1_Paper_1.png?locale=en-gb&auto=webp&format=jpeg&width=216&height=124&quality=90&fit=bounds)
![45345_Science_U5_L1_Paper_1.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltc2971449043b24da/628e0e79bde8395bd0124e20/45345_Science_U5_L1_Paper_1.png?locale=en-gb&auto=webp&format=jpeg&width=216&height=124&quality=90&fit=bounds)
![45345_Science_U5_L1_Paper_2.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blta2b70aabc99d0d42/628e0e79af7b396927eddbaf/45345_Science_U5_L1_Paper_2.png?locale=en-gb&auto=webp&format=jpeg&width=216&height=124&quality=90&fit=bounds)
Does the position change how well the fan works to blow over the tower?
08
![Explain_Maria.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blt11a8cb2ae0506666/62710efebae21939d5444d60/Explain_Maria.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Use your model to explain how your fan can move air particles.
09
![Explain_Maria.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blt11a8cb2ae0506666/62710efebae21939d5444d60/Explain_Maria.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Use your model to explain how your fan can blow over a paper tower without touching it.
10
![MicrosoftTeams-image_(4).png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltb3b6bb58fa99ec1b/629470e531e9d30f65bee2a5/MicrosoftTeams-image_(4).png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Use cardboard or other materials to design a better fan blade, and then test again to see what happens.
11
![GslastEssentialMinifig.518563b8.png](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blt8a54880687149983/62710efefbd1dd35f419cee2/GslastEssentialMinifig.518563b8.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Great job!