Lesson: The Awesomely Evolved Human Brain

First published 2013. To view the latest Heads Up content, click here.
Use the lesson and student work sheet below to reinforce comprehension of key facts and concepts in the student article “The Awesomely Evolved Human Brain.”

Dear Teacher:

This year’s Heads Up series focuses on the human brain and gives students an abundance of valuable information through expertly crafted infographics. We start off with an article about the amazing abilities of the human brain in the context of the evolution of the brain’s reward system. Unhealthy behaviors, like using drugs and eating large quantities of unhealthy food, can overload the reward system, throwing us out of balance and possibly into jeopardy.

In the accompanying work sheet, we put students’ brains to the test and demonstrate for them, in real time, the brain’s remarkable ability to make predictions and solve ambiguities, and help students to better understand how drugs might compromise these capabilities.

By sharing these important materials with your students, you are helping them understand how to protect one of their most valuable assets—their brains!

In This Installment:

  • Student article: Students will understand that the brain’s reward system has evolved to help ensure the survival of the species. Drugs can overload the reward system and decrease the brain’s protective abilities. Click here for a version of the article adapted for struggling readers.
  • Student work sheet: Students will solve brainteasers and answer critical-thinking questions about how drugs interfere with specific abilities in real-world situations.

Supports CCSS & NGSS Standards
Visit scholastic.com/headsup/standards for a standards chart.

Lesson Plan

Before-Reading Questions:

  • How do you think your brain might be involved in making decisions about what to eat?
  • What do you know about how your brain processes information and comes to conclusions?
  • What do you know about how you can keep your brain’s natural chemicals in balance?
  • What do you know about how drugs work inside the brain?

After-Reading Questions (factual responses in italics):

  • What is homeostasis and why is it important? (Homeostasis describes a person’s internal environment when that environment is stable and balanced. When in balance, the brain is capable of amazing feats of intelligence, giving people the best chance of succeeding in school and life. Drugs or foods that result in unbalanced dopamine levels can cause physical changes to the brain that detract from achieving success.)
  • How can you keep your brain in balance? (Keep dopamine levels in balance by eating moderate portions of healthy foods and consuming processed treats on occasion. Avoid drugs.)
  • How might drugs interfere with how the brain works? (Drugs can turn the natural chemical process that produces healthy dopamine levels to reward behaviors into one that releases abnormally high dopamine levels, resulting in compulsive behavior. The unnaturally large dopamine spikes cause your brain to adapt to this new, larger amount of dopamine so that you need large amounts of dopamine just to feel normal.)
  • What is the connection between eating unhealthy foods and using drugs? (Both involve overloading the brain with dopamine and upset the balance of the brain’s reward system.)
  • Considering the evolutionary timeline of the human brain, what is unique about the last 500 years? (The last 500 years are marked by an overload of influences on the brain, the most in the entire evolutionary history of the brain.)

Student Work Sheet

Have each student complete the work sheet individually. Evaluate students on their ability to construct evidence-based answers using information from the text and their own inferences.

View the Student Work Sheet online (HTML).
Download and print the Student Work Sheet (PDF).

Work Sheet Answer Key:

  • Brainteasers

Double Take: dish, goblet, or table; two profiles.

Spell Check: “Don’t even think of eating this! It’s cheese with fuzzy mold for my science project!”

  • Think It Through
  1. Drugs can alter your perceptions and slow your reflexes so that you are unable to adapt to changes as you are driving.
  2. Drugs can interfere with the processes required to retain information. They can decrease the brain’s ability to fill in missing information by seeing patterns, which interferes with problem solving on a test.
  3. The brain has systems in place for avoiding injury, like the reflex response and the ability to predict potential danger in the environment. Drugs interfere with those capabilities.


More Information


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The student article and Teacher’s Guide PDFs meet Section 508 accessibility guidelines.

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