The Longest Step

What is Length?
Length tells us how long or short something is. It is the distance from one end of an object to the other.

Tools to measure length
Common tools are a ruler (in centimetres and millimetres), measuring tape (for metres), and a piece of string (for curved objects).

How to measure with a ruler (step-by-step)

1. Place the object on a flat surface.
2. Keep the ruler straight and align the 0 mark of the ruler with one end of the object.
3. Read the number on the ruler at the other end of the object — that tells the length.
4. If the object is longer than the ruler, use a measuring tape or mark and continue from the last mark.
5. For curved items, wrap a string around them, then measure the string with a ruler.

Units of length (simple)
We usually use millimetres (mm), centimetres (cm), and metres (m). For Class 2, we commonly use centimetres and metres. Always write the unit with the number, for example 12 cm.

Tips and common mistakes

• Start measuring from the 0 mark, not from the side of the ruler that has no mark.
• Keep the ruler straight and flat on the object.
• Do not guess beyond the last clear mark — estimate to the nearest mm or cm if needed.

Comparing lengths
To find which object is longest, measure each object and compare the numbers. The bigger number means the object is longer.

What are non-standard units? Non-standard units are everyday objects used to measure length (or other quantities) instead of centimetres or metres. Examples: paperclips, pencils, hand-spans, footsteps, cubes. They are useful for young children to learn measurement ideas.

How to measure with non-standard units (step-by-step)

• Choose one object to be your unit (for example, a pencil).
• Place the first unit at one end of the object being measured. Make sure its end lines up exactly with the start.
• Place more units end-to-end without gaps or overlaps until you reach the other end.
• Count how many complete units fit along the object. If there is a small part left, say there is a remainder (e.g. 5 full pencils and a little more).
• Always use the same unit for comparison. Do not mix units when comparing lengths.

Rules and tips

• Use identical items as units (all pencils the same, or all hand-spans by the same person).
• Start measuring from the same point (edge) each time.
• Do not leave gaps or overlap units while measuring.
• To compare two objects, measure both with the same non-standard unit and compare the counts.

Why learn non-standard units? They help children understand length, counting and comparison before they learn centimetres and metres. They also introduce ideas of addition and subtraction of lengths.

Limitations:

• Different units (different pencils, different people’s hand-spans) give different results.
• They are not precise for exact scientific measurement but are great for learning concepts.

What is length? Length tells us how long or short something is. We use words like longer, shorter, longest, shortest and same (equal) length.

How we compare lengths

• Direct comparison: Place two objects side by side with one end lined up. The one whose other end goes farther is longer.
• Using a ruler or tape: Put the object against a ruler, read the number at the far end to find its length in units (cm or m). Make sure both objects are measured using the same units before comparing.
• Using non-standard units: For young children we can measure with paper clips, hand spans, or steps. Count how many of the same unit fit along the object.

How to order objects by length: Measure or compare each object, then arrange from shortest to longest (or longest to shortest). If two measures are equal, they have the same length.

Tips for accurate comparison: Always start measuring from the zero mark on the ruler, align ends carefully, and use the same unit for both objects.

Using steps to measure means finding how far something is by counting how many steps you take from one point to another. It is a simple way to measure when a ruler or tape measure is not available. Each person’s step (also called stride) has a length. If you know the length of one step, you can multiply it by the number of steps to get the total distance.

How to do it:

• Decide whether you will use small steps or big steps and use the same type throughout.
• Measure and find the length of one step (for example, one step = 50 cm). You can do this by walking a known distance (like 10 m), counting the steps, and dividing: step length = total distance ÷ number of steps.
• Walk from the start to the end point counting your steps.
• Calculate distance = number of steps × length of one step.
• If you get a partial step at the end, estimate the fraction (for example, half a step = 0.5 × step length).

Tips for better accuracy: use the same person to measure, keep steps steady, measure step length more than once and take an average, and walk in a straight line.

What is Ordering by Length?

Ordering by length means putting objects in order from shortest to longest or longest to shortest. We look at how long each object is and then arrange them accordingly.

How to compare lengths (simple steps):strong>

• Choose a way to measure — either a ruler (standard unit) or a non-standard unit like paperclips or handspans.
• Align one end of each object at the same starting point (baseline) so the comparison is fair.
• See which object reaches the farthest — that is the longest. See which reaches the least — that is the shortest.
• If you measure, write the lengths (for example, 3 cm, 7 cm) and then arrange from smallest to largest or vice versa.

Why align at one end? If objects are not aligned, you may get a wrong idea of which is longer. Aligning gives a correct visual comparison.

Using symbols: We use < to mean shorter than, > to mean longer than, and = to mean equal in length. Example: pencil A (5 cm) < pencil B (8 cm).