Praxis Core Reading Practice Test: Main Idea and Supporting Details

City planners once valued street trees mainly for their looks. That view has changed. On a summer afternoon, a street lined with mature trees can be several degrees cooler than a nearby street without shade, and the roots of those trees soak up rainwater that would otherwise rush into storm drains. Because these benefits grow as a tree gets older, many cities now protect older trees during construction instead of replacing them with young saplings.

City planners once valued street trees mainly for their looks. That view has changed. On a summer afternoon, a street lined with mature trees can be several degrees cooler than a nearby street without shade, and the roots of those trees soak up rainwater that would otherwise rush into storm drains. Because these benefits grow as a tree gets older, many cities now protect older trees during construction instead of replacing them with young saplings.

When the Millbrook Public Library opened a seed library, the staff expected a handful of gardeners to borrow packets of tomato and bean seeds. Within a year, more than four hundred residents had signed up. Borrowers take seeds in the spring, grow the plants, and return seeds saved from their harvest in the fall. The returned seeds come from plants that have already done well in local soil, so each year's collection is a little better suited to the town's climate than the last.

When the Millbrook Public Library opened a seed library, the staff expected a handful of gardeners to borrow packets of tomato and bean seeds. Within a year, more than four hundred residents had signed up. Borrowers take seeds in the spring, grow the plants, and return seeds saved from their harvest in the fall. The returned seeds come from plants that have already done well in local soil, so each year's collection is a little better suited to the town's climate than the last.

Before the Erie Canal opened in 1825, moving goods by wagon from Buffalo to New York City was slow and expensive. The canal cut both the travel time and the cost sharply, and New York City soon became the busiest port in the nation. Towns along the route, such as Rochester and Syracuse, grew quickly as farmers and manufacturers gained an easy way to reach eastern markets.

Before the Erie Canal opened in 1825, moving goods by wagon from Buffalo to New York City was slow and expensive. The canal cut both the travel time and the cost sharply, and New York City soon became the busiest port in the nation. Towns along the route, such as Rochester and Syracuse, grew quickly as farmers and manufacturers gained an easy way to reach eastern markets.

Octopuses can change the color and texture of their skin in a fraction of a second. Special cells called chromatophores, each holding a small sac of pigment, expand or shrink when tiny muscles around them contract or relax. Researchers were surprised to learn that octopuses appear to be color-blind in the usual sense, since their eyes have only one type of light receptor. How these animals match colors they may not be able to see is still being studied.

Octopuses can change the color and texture of their skin in a fraction of a second. Special cells called chromatophores, each holding a small sac of pigment, expand or shrink when tiny muscles around them contract or relax. Researchers were surprised to learn that octopuses appear to be color-blind in the usual sense, since their eyes have only one type of light receptor. How these animals match colors they may not be able to see is still being studied.

Many students assume that rereading a chapter is the best way to prepare for a test. Rereading feels productive because the material starts to look familiar. Yet familiarity is not the same as being able to recall information without help. Practice that makes students pull answers from memory, such as answering questions with the book closed, tends to produce longer-lasting learning, even though it feels harder at the time.

Many students assume that rereading a chapter is the best way to prepare for a test. Rereading feels productive because the material starts to look familiar. Yet familiarity is not the same as being able to recall information without help. Practice that makes students pull answers from memory, such as answering questions with the book closed, tends to produce longer-lasting learning, even though it feels harder at the time.