August 21

High school (ages 12+)
Mathematics & Numbers

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/august-21

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the day of year (common year)?233rd day
2. What is the day of year (leap year)?234th day
3. Why is August 21 special?It marks the 233rd day, which is a prime number, and shows how the calendar keeps time with the Earth's orbit.
4. How does a leap year change August 21?In a leap year, August 21 becomes the 234th day because an extra day is added to keep the calendar in sync with the Earth's orbit.

Gregorian calendar: The solar calendar currently used in most of the world, established to correct inaccuracies in the Julian calendar.
Tropical year: The time it takes for the Sun to return to the same position in the cycle of seasons, approximately 365.2422 days.
Prime number: A natural number greater than 1 that has no positive divisors other than 1 and itself, fundamental in number theory and cryptography.
Cryptography: The science of secure communication, heavily reliant on the properties of prime numbers for encryption and decryption.