4
How they Work? Trains
4
Niagara Falls
4
Okavango Delta, Botswana
3
Neil Armstrong
4
Mount Fuji, Japan
3
Motion
2
Lake Day
4
Felix's Independence Day
3
Police Officer
3
Space Exploration
3
Firefighter
3
Pollution
3
Astronauts
3
Meteorites, Meteoroids, and Meteors
3
Bus Driver
4
Hoover Dam
4
Maddy's New Hampshire Diary
4
Victoria Falls, Zimbabwe/Zambia
4
Gorillas and Other Primates
3
Comets
2
Who Works Here?