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Self-Correct as You Read is a free printable Grade 4 English worksheet on going back over an information text to fix understanding, aligned to Common Core standard RF.4.4. It prints 2 questions with an answer key on its own sheet of paper, in 25 versions that each ask different questions, so no two pupils in the class work from the same page. Print it from the browser or download it as a PDF — no account, no email.

Set 18 of 25 · the same problems every time you open this link.

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Set 1 has all 25 in a single PDF. All 25 sets ask different questions.

Self-Correct as You Read

RF.4.4

NameDate

Read the text, then answer the questions.

1.Read the text, then answer the questions.

How Penicillin Was Found

In 1928 Alexander Fleming went on holiday and left a stack of dishes on a bench. Each held a colony of bacteria. When he came back, one dish had a spot of mould on it. Around the mould was a clear ring where the bacteria had died. Fleming realised the mould was producing something that killed bacteria. He named it penicillin and published a paper. Almost nobody noticed. Ten years later, Howard Florey and Ernst Chain read that paper and tried to make penicillin in quantity. That turned out to be the hard part: it took two thousand litres of mould fluid to treat one patient. By 1944 the problem had been solved and penicillin was reaching soldiers in the field.

  1. 1. How much mould fluid did it take to treat one patient?
  2. 2. What did he see around the mould?
  3. 3. What is a "colony" of bacteria?
  4. 4. In what year did Fleming notice the mould?
2.Read the text, then answer the questions.

What a Beaver Dam Does

A beaver does not build a dam for shelter. It builds one to make a pond, and it lives in a lodge in the pond. The dam raises the water so the lodge entrance stays underwater. A predator that cannot swim cannot get in. But the pond does far more than protect one family. Behind a dam, water slows, and slow water drops the silt it carries. Over years this builds rich wet ground. That ground holds water in a drought and holds it back in a flood. It supports plants, insects, amphibians and birds that were not there before. Where beavers have been reintroduced, the number of species in a valley typically rises within five years.

  1. 1. Why does a beaver build a dam?
  2. 2. What is "silt"?
  3. 3. What is a "lodge"?
  4. 4. What keeps a predator out of the lodge?

LessonPrint · RF.4.4 · Set 18 · free to copy for classroom use

Answer key — Self-Correct as You Read

Set 18. Prints on its own sheet.

  1. 1.1. Two thousand litres. 2. A clear ring where the bacteria had died. 3. A group of bacteria growing together in one place. 4. 1928.
  2. 2.1. To make a pond — it lives in a lodge in the pond. 2. Fine soil carried along by moving water. 3. The beaver's home in the pond, entered from underwater. 4. The entrance stays underwater because the dam raises the water.

Last reviewed 2026-09-05. Aligned to RF.4.4 of the Common Core State Standards for English language arts.