K-5 friendly lesson
One small step at a time.Read the idea, try the activity, and celebrate each win as you go.
Muscles Work in Pairs
When one muscle pulls, its partner relaxes.
Do this: Read the concept below, then try the quiz or activity.
Lesson 6 of 18
Concept
Muscles move bones by pulling. Pairs like biceps and triceps work together: one contracts while the other relaxes.
Short Answer
Explain how biceps and triceps move your arm.