Indiana Science MS-PS2-3

Science7th GradePhysical Science

The Standard

Ask questions and design a plan to determine the factors that affect the strength of electric and magnetic forces. [Clarification Statement: Examples of devices that use electric and magnetic forces could include electromagnets, electric motors, or generators. Examples of data could include the effect of the number of turns of wire on the strength of an electromagnet, or the effect of increasing the number or strength of magnets on the speed of an electric motor.]

Indiana Academic Standards for Science (2023) · Motion and Stability: Forces and Interactions

Teacher's field guide

What This Standard Means

What Students Need to Do: Students ask what makes an electric or magnetic pull stronger. They plan a test that changes one factor, measures the pull, and keeps other conditions the same.
What Mastery Looks Like: A student can plan a test of 10 versus 20 wire turns using the same nail and battery. They repeat the test, record how many paper clips lift, and use the counts to explain which setup pulls harder.
Common Misconceptions: Students may think a magnet must touch an object to pull it. They may change both the wire turns and the battery, then claim the turns alone caused the result.
How to Assess It: Exit ticket: “Does a nail electromagnet lift more paper clips with 10 or 20 wire turns? Describe what you would change, measure, and keep the same.”

Lesson moves

Ways to Teach It

Wrap 10 or 20 turns of insulated wire around one nail, briefly connect each coil to the same battery, and count lifted paper clips.
Ask: “Why can't we change both the wire turns and the battery if we want to know what made the magnet stronger?”
Give pairs cards marked wire turns, nail size, battery, and clips lifted; have them sort what to change, keep fixed, and measure.
For laundry cling, rub a balloon on wool 5 or 15 times, then count tissue bits attracted from 2 cm.

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