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About Time

How has the pace of human innovation changed over time?

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About Time

How has the pace of human innovation changed over time?

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How has the pace of human innovation changed over time? It took 260,000 years for humans to go from the spear to the bow-and-arrow, but only 42,000 years to go from the bow-and-arrow to the atomic bomb.

Students order and subtract integers to explore major milestones in human history and debate whether humans are innovating faster than we can keep up with the consequences.

REAL WORLD TAKEAWAYS

  • Humans have been making technological innovations throughout history – in communication, in travel, in warfare. Over time, advancements from one milestone to the next have come more and more quickly.
  • Future innovations – like those of the past – will likely offer convenience and meaningful enhancements to our lives; they may also come with serious dangers. It’s important for society to anticipate, consider, and discuss these impending risks.

MATH OBJECTIVES

  • Model “before zero” years using negative integers
  • Order and position positive and negative integers on a number line
  • Find the difference between integers, including negatives

Appropriate most times as students are developing conceptual understanding.
Lesson gauge medium
Grade 7
Rational Numbers
Lesson gauge medium
Grade 7
Rational Numbers
Content Standards 7.NS.1 Apply and extend previous understandings of addition and subtraction to add and subtract rational numbers; represent addition and subtraction on a horizontal or vertical number line diagram. (a) Describe situations in which opposite quantities combine to make 0. For example, a hydrogen atom has 0 charge because its two constituents are oppositely charged. (b) Understand p + q as the number located a distance |q| from p, in the positive or negative direction depending on whether q is positive or negative. Show that a number and its opposite have a sum of 0 (are additive inverses). Interpret sums of rational numbers by describing real-world contexts. (c) Understand subtraction of rational numbers as adding the additive inverse, p — q = p + (‐q). Show that the distance between two rational numbers on the number line is the absolute value of their difference, and apply this principle in real-world contexts. (d) Apply properties of operations as strategies to add and subtract rational numbers. 7.NS.3 Solve real-world and mathematical problems involving the four operations with rational numbers.
Mathematical Practices MP.2 Reason abstractly and quantitatively. MP.3 Construct viable arguments and critique the reasoning of others. MP.4 Model with mathematics. MP.5 Use appropriate tools strategically.

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