Electricity and Magnetism · Weeks 19-27

Parallel Circuits

Building and calculating properties of parallel circuit configurations.

About This Topic

Scientific notation is a way to express very large or very small numbers using powers of ten. In 9th grade, students apply their knowledge of exponent laws to perform calculations with these numbers in the context of science. This topic is a key Common Core standard that connects 'Number and Quantity' to real-world applications in astronomy, biology, and chemistry.

Students learn that multiplying numbers in scientific notation involves multiplying the coefficients and adding the exponents. This makes it possible to compare the scale of a single cell to the scale of the entire Milky Way galaxy. This topic comes alive when students can engage in 'scale simulations' or collaborative investigations where they use scientific notation to solve 'Fermi problems', complex estimation challenges that require thinking in powers of ten.

Active Learning Ideas

Simulation Game: Scaling the Universe

Groups are given objects ranging from an atom to the sun. They must research their sizes, write them in scientific notation, and then 'order' them on a giant classroom timeline of scale, explaining the massive jumps in powers of ten between them.

⏱ 40 min·Small Groups

Generate mission

Inquiry Circle: Fermi Problems

Students work together to solve 'impossible' questions like 'How many grains of sand are on a beach?' They must use scientific notation to make reasonable estimates for each part of the problem and multiply them to find a final answer.

⏱ 35 min·Small Groups

Generate mission

Think-Pair-Share: Significant Figures Check

Give students a calculation in scientific notation. One student performs the math, while the other checks that the final answer is written correctly (with only one digit before the decimal) and discusses how many 'significant figures' should be kept.

⏱ 20 min·Pairs

Generate mission

Watch Out for These Misconceptions

Common Misconception

Students often think that a larger negative exponent means a larger number (e.g., thinking 10^-5 is bigger than 10^-2).

What to Teach Instead

Use the 'Scaling the Universe' activity. Peer discussion about 'place value' helps students realize that 10^-5 means the decimal is five places to the left, making it a much smaller fraction than 10^-2.

Common Misconception

Forgetting to adjust the coefficient after a calculation (e.g., leaving an answer as 15 x 10^4).

What to Teach Instead

Use 'Think-Pair-Share' to reinforce the 'standard form' rule. Students must check each other's work to ensure the coefficient is always between 1 and 10, adjusting the exponent accordingly (e.g., 1.5 x 10^5).

Frequently Asked Questions

Why do scientists use scientific notation?

It makes it much easier to work with extreme numbers without having to count dozens of zeros. It also allows scientists to clearly show the 'precision' of their measurements using significant figures.

How can active learning help students understand scientific notation?

Active learning strategies like 'Fermi Problems' take scientific notation out of the textbook and turn it into a tool for exploration. When students have to estimate the number of atoms in a drop of water, they realize that standard numbers are useless for the task. This 'need' for a better system makes the rules of scientific notation feel like a powerful upgrade to their mathematical toolkit.

How do you add or subtract numbers in scientific notation?

To add or subtract, the exponents must be the same. You may need to rewrite one of the numbers so their powers of ten match before you can add or subtract the coefficients.

What is a 'power of ten'?

A power of ten is 10 raised to any exponent. Each increase in the exponent (from 10^2 to 10^3) represents a value that is ten times larger than the one before it.

Browse curriculum by country

• Americas
• US
• CA
• MX
• CL
• CO
• BR

• Europe
• UK
• IE
• FR
• DE
• ES
• IT
• NL
• PT
• SE

• Asia & Pacific
• IN
• SG
• AU