Toggle Navigation
Games
Blog
News
Class PIN
Join for Free
Sign in
Toggle Navigation
Games
PIN
Join for Free
Blog
Pricing
News
Contact us
Help center
Sign in
Study
Inventions
0
%
0
0
0
Back
Restart
What's this?
invitation
Oops!
Okay!
What's this?
wheel
Oops!
Okay!
What's this?
accident
Oops!
Okay!
Discovery or invention?
discovery
Oops!
Okay!
What's this?
electricity
Oops!
Okay!
What's this?
refrigerator / fridge
Oops!
Okay!
What's this?
bathtub
Oops!
Okay!
What's this?
medicine
Oops!
Okay!
Who's he?
Newton
Oops!
Okay!
What's this?
gravity
Oops!
Okay!
Your experience on this site will be improved by allowing cookies.
Allow cookies