Free printable SSAT practice test for Grade 3

The roof of Leo's apartment building was flat, gray, and boring. It had a few old chairs, a rusty railing, and a view of other flat, gray, boring roofs.

"It needs something," Leo told his neighbor, Mr. Kim, who sometimes read his newspaper up there.

"Like what?" asked Mr. Kim.

"Tomatoes," said Leo. "And sunflowers. Maybe beans."

Mr. Kim lowered his newspaper. "Do you know how heavy a pot of wet soil is?"

Leo did not. So Mr. Kim showed him. Together they filled one bucket with soil and watered it, and Leo could barely lift it. "That's why you plan first," Mr. Kim said. "A roof can only hold so much weight."

They asked the building manager, who said yes as long as they kept the pots near the edges, where the roof was strongest. They used light plastic pots instead of clay ones. Leo made a chart of how much sunlight each corner got, and they put the tomatoes in the sunniest spot.

The first weeks were hard. A windy day knocked over the bean plants, so Leo and Mr. Kim tied them to sticks. A heat wave dried out the soil, so they took turns watering every evening.

By August, the gray roof was green and yellow. Neighbors came up to sit among the sunflowers. One evening, Leo handed Mr. Kim a bright red tomato.

"Not boring anymore," Mr. Kim said, smiling.

A honeybee that finds a field full of flowers has a problem. The hive may be far away, and thousands of other bees need to know where the food is. Bees cannot talk, and they cannot draw a map. So how does one bee tell the others where to go?

The answer is a dance. When a worker bee returns to the hive, she moves across the honeycomb in a special pattern called the waggle dance. She walks forward in a straight line while shaking her body from side to side. Then she circles back and does it again, over and over.

Every part of the dance carries information. The direction of the straight walk tells the other bees which way to fly, compared with the position of the sun. If the bee walks straight up the honeycomb, the flowers are in the same direction as the sun. If she walks a little to the right, the flowers are a little to the right of the sun.

The length of the waggle tells how far away the flowers are. A short waggle means the food is close. A long waggle means the bees will need to fly a longer way.

Other worker bees crowd around the dancer and follow her movements. They also smell the flowers' scent on her body. Then they fly out of the hive, ready to find the field on their own.

Scientists who study bees were amazed when they first figured out this dance. It showed that even a tiny insect can share exact, useful information with the rest of its group.

When you drop a newspaper into a recycling bin, its journey is just beginning. Within a few weeks, that same paper could come back as a cereal box, a paper towel, or a page in a notebook.

First, a truck collects the paper and takes it to a recycling center. There, workers and machines sort it. Newspapers go in one pile, cardboard in another, and office paper in a third, because each kind is made a little differently.

Next, the sorted paper goes to a paper mill. It is dropped into a giant tank of water and stirred until it breaks apart into a mushy mixture called pulp. The pulp looks a little like oatmeal.

The pulp is then cleaned. Screens catch staples, tape, and bits of plastic. Sometimes soap and air bubbles are used to lift the ink out, the same way soap lifts dirt from your hands.

After cleaning, the pulp is spread out in a thin layer on a moving screen. Water drains away, and heavy rollers squeeze and dry the paper until it becomes a long, smooth sheet. The sheet is wound into huge rolls and sent to factories that turn it into new products.

Paper cannot be recycled forever. Each time it goes through the process, its tiny fibers get shorter and weaker. But every time it is recycled instead of thrown away, fewer trees need to be cut down to make new paper.