Subscribe

3rd grade · Science · Unit 4 of 8

Speed & Motion

Fast and slow, why things keep moving, and what changes how quickly motion changes.

What your child practices

Practices speed as the distance an object travels in a certain time, inertia (objects keep doing what they are doing until a force acts), and how mass and force affect how quickly motion changes.

Maine Learning Results learning standard: 3-PS2-1; 3-PS2-2 · how forces change motion and patterns that predict motion

How we explain it

Children can open this short lesson before they practice.

  1. Speed is how far something travels in a certain time.
  2. Things keep doing what they are doing until a force acts on them.
  3. Friction slows things down. Rough grass has more friction than smooth ice.

Example: A runner goes 10 km in one hour. A walker goes 5 km. Who is faster? Both took one hour. 10 km is farther than 5 km. Answer: the runner

Speed & Motion in Maine

In the Maine Learning Results, this is unit 4 of 8 in 3rd grade Science, after Basic Needs & Life Cycles and before Traits & Variation.

Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.

Source: Maine Department of Education

Sample questions

A taste of this unit. In the app, questions change every time and get easier or harder to match your child.

  1. Question 1

    Which unit could measure how far something travels?

    • kilograms
    • meters
    • seconds

  2. Question 2

    You are in a car that suddenly stops. Your body leans forward because of…

    • cold weather
    • inertia
    • hunger

  3. Question 3

    Speed tells us…

    • what color it is
    • how heavy it is
    • how fast something moves

  4. Question 4

    After you stop pedaling, a bike slows down because of…

    • friction and air
    • more energy
    • it getting younger

  5. Question 5

    A car travels 60 km in one hour. A bike travels 15 km in one hour. Which has greater speed?

    • they are the same
    • the car
    • the bike

  6. Question 6

    Runner A goes 100 m in 20 s. Runner B goes 100 m in 25 s. Who is faster?

    • Same
    • Runner B
    • Runner A

More 3rd grade