How fast was the wind speed of Hurricane Harvey?

Grade level:  5th – 6th grades

Skills: Measurement (Speed)

Hurricane Harvey landed in Texas on August 25, 2017. It became one of the most destructive hurricanes that made landfall in the United States. Hurricanes are categorized into one of 5 classification based on a hurricane’s wind speed.  The table below shows the 5 categories and their potential damage caused by winds.

Screen Shot 2017-09-26 at 10.26.01 AM

  1. Maximum wind speed in Harvey’s eyeball was measured 130 mph (miles per hour). Which category does Harvey belong to?
  2. How fast did winds in Harvey’s eyeball move per minute? Round the number to the nearest whole number.
  3. Hurricane Maria landed in Puerto Rico on September 20, 2017. Maria made landfall as a Category 4 hurricane. What kind of potential damage did Maria give to the houses and trees in Puerto Rico?

Sources: National Hurricane Center


Answer keys

  1. Category 4
  2. 130 ÷ 60 ≈ 2
  3. Potential damage to houses: Loss of most of the roof structure and/or some exterior walls                   Potential damage to most trees:  snapped or uprooted


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    (

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 &


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)