Two excellent watery demonstrations this week!
A resource I use regularly to demonstrate ‘real life graphs’ comes from the excellent CLEO Resources (Cumbria and Lancashire Education Online).
Fill the various flasks with water and investigate how the height of the water varies with time.
Fill a shape with water then drag it to another shape to empty the water into that shape!
(Other activities I particularly like on this site include tessellations and the isometric drawing tool from the 6th grade resources, Virtual Box from the 7th Grade resources and the Painted Cubes investigation from the 8th Grade resources.)