Having students create their own ruler is a great way to get them to understand how a ruler works. There are two types of rulers: The average foot long ruler and the metric ruler. Both rulers can be made in the classroom and then sealed with a laminating machine. Students can use their nerwly created rulers throughout the school year.
Things You'll Need
 Poster board
 Ruler
 Laminating machine
 Markers
 Scissors
Foot Long Ruler

Hand out a regular foot long ruler to each student. Instruct the children to trace the edges of the ruler onto a piece of poster board.

Cut the ruler out with a pair of scissors.

Begin by teaching the children about inches. Have them hold the ruler up to the cut out poster board and mark every 12inch segment. Explain that the inch mark is the longest mark on a foot long ruler.

Show the students the half inch mark. Explain that these are the second longest marks on this type of ruler. Have the students insert the half marks.

Show each student the small marks in between the half marks. Tell them that each of these marks counts as 1/10th of the whole inch. That means every 10 marks equals one inch. Have the children draw in the small marks.
The Metric Ruler

Flip the ruler you just created over and take out a metric ruler.

Explain to the students that the metric ruler has only centimeters and millimeters. Explain that centimeters are identified by the larger marks. Have the children locate the marks and then copy them onto their poster board rulers. Explain that this ruler is going to be 30centimeters long because you have already cut it to be exactly 1foot long.

Find the smaller marks and then explain that these are millimeters. Have the students copy the millimeters.

Laminate each ruler with a laminating machine. This will protect each ruler from spills and normal wear and tear.