Which endangered animal is heavier, Tiger or Leopard?

Grade level: 4th – 5th grades

Skills: Bar graphs

Related environmental issues: Biodiversity

As many as 26,000 species are threatened with extinction in the world because people have changed their habitats, and they lost their homes. The bar graph below shows the weight of some of the most endangered  animals in the world.

Screen Shot 2018-11-09 at 12.21.09 PM

1.Among the endangered animals, which animal weighs the most?

2.Which is heavier, Amur Leopard or Sumatran Orangutan?

3.Which endangered animal weighs twice as much as Hawksbill Sea Turtle?




Answer keys


1.Mountain Gorilla

2.Sumatran Orangutan

3.South China Tiger



Endangered coral reef in Australia

Grade level:  5th – 6th grades

Skills: Measurement (unit conversion) 

Related environmental issues: Biodiversity

The Great Barrier Reef in Australia–the  biggest coral reef system in the world– is home to about 400 types of coral and 1,500 fish species.  However, the corals there have been killed by overheated seawater resulting from recent climate change. Terry P. Hughes, a researcher of coral reef, reported that 67 percent of the corals had died in the north of the Great Barrier Reef.


healthy coral (National Geographic)


dying (left) and dead (right) coral    (abc.net.au)

Convert into given unit of measurement.

  1. The Great Barrier Reef stretches more than 1,600 miles.  1,600 miles = ________ km
  2. The Great Barrier Reef stretches more than 1,600 miles.  1,600 miles = ________ feet
  3. About 13,000 years ago, the sea level of Australia was 200 feet lower than the current level.    200 feet = ______ inches
  4. The observations suggested that 20% of coral in the central area of the 344,000 sq km reef is dead.     344,000 sq km = _______ sq miles

1 mile =  1.61 km

1 mile = 5,280 feet

1 foot = 12 inches

1 sq km = 0.39 sq miles


Sources: NY Times, March 15, 2017, Life Science & News.com.au


Answer keys

  1. 1,600 x 1.61 = 2,576  (km)
  2. 1,600 x 5,280 = 8,448,000 (feet)
  3. 200 x 12 =2,400 (inches)
  4. 344,000 x 0.39 = 134,160 (sq miles)