The Discovery Class has been inventing!  Here are some of their inventions, from Upper-left, clockwise,

Planet Bracelet, Annika

Jupiter and Equal, the planets

Eyeball Plate, Gavin 

It shakes the eyes

Spoon and Lightcatcher, Jo

A special spoon that catches the light

And a waterwall

Mirror, Hugo

A special mirror you can see pieces

Of yourself in