CAASPP Success - Grade 3 Reading Comprehension - Expository #2

A mechanical gear system

A system of candles

A method to harness the sun's energy

Sundials were the primary way to tell time in ancient Egypt.

Mechanical clocks were first developed during the Middle Ages.

Obelisks were built to cast shadows and tell time.

A modern digital device

A tool used by ancient Egyptians

A new method of casting shadows

They were more accurate when placed high up.

They were used for worship services only.

They were built as symbols of faith.

The use of sundials and water clocks

The building of obelisks and towers

The introduction of pocket watches

Sundials and Water Clocks

Obelisks and Candle Clocks

Pocket Watches and Mechanical Clocks

They often broke down and needed repair.

They used a lot of energy to operate.

They were too small to read from a distance.

It introduced the concept of using quartz crystals in timekeeping.

It made mechanical clocks smaller and more portable.

It allowed clocks to be placed in people’s homes.

To make the passage seem more scientific

To introduce a difficult concept

To summarize the main idea

Early timekeeping involved using the sun and stars, and this method is still widespread today.

Water clocks were only used by the Greeks in the past, but now many different cultures use them.

Mechanical clocks were more accurate than previous methods, and they are still the most accurate.