Grade 2 · Math · Lesson 28

Measure with Rulers Accurately

A ruler is a measuring tool marked with two scales. In the United States, a standard ruler shows inches (in) along the top edge and centimeters (cm) along the bottom edge. Measuring accurately means following three rules every time.

What this lesson teaches

1Place a ruler correctly with the zero mark at the start of an object
2Read the inch or centimeter mark at the other end to find the length
3Know common classroom-object lengths in inches and centimeters
4Read both edges of a dual-scale US ruler (inches on top, centimeters on bottom)

Free · 7 days · No credit card

Unlock the full HSEA system for 7 days.

Create a kid profile, open any lesson, save progress — your family uses HSEA exactly the way a paying family does. Cancel anytime. Nothing to set up, no card required.

✓ All 1,680 lessons, Grades 1–6, every subject
✓ Profiles + saved progress for every kid
✓ Final exams + printable certificates

Start your 7-day free trial →

Already convinced? See full membership plans →