hey there it's Kalei in this lesson we're going to learn to measure to the
whole inch let's get started we have learned to measure things by lining up
boxes and counting how many high or how many long the lines are we can see that
the orange line is four boxes long and the pink line is two boxes long now that
we know how to measure with boxes we can switch out the boxes for a measuring
tool called a ruler a ruler is a straight stick that has specific lengths
marked on it the lengths we are going to talk in this lesson are inches on this
ruler inches are marked along the top starting at 0 and going all the way to
12 inches the distances between each number is exactly the same that distance
is called an inch we can write the units as in for short when talking about
measurements we use rulers to measure the same way we use the blocks if I want
to know how long this rectangle is I first need to line up the edge of my
rectangle right at the zero point on my ruler then I can count how many inches
there are until the end of my rectangle and since rulers are numbered I can find
the edge of my rectangle and see where it lands on my ruler 9 inches so this
pink rectangle is 9 inches long now I'm trying to measure the green rectangle
and I can see that I'm getting a length of 8 inches but is this the correct
length you don't think so why not that's right I didn't line up the end of my
rectangle with the 0 in mark if I bring my rectangle back to the
zero inch mark I can see that my rectangle is really only seven inches
long here we're going to measure the green line with boxes and a ruler how
many boxes long is the green line remember we can count them and we get
five boxes now if we measure the line with the ruler how many inches is it
we've started at zero inches and we see it goes all the way to six inches so
what can I say about the lengths of the boxes is each box longer or shorter
than one inch they are longer than one inch
because only five boxes are needed to find the length of the line but six
inches are needed to find the length of the line now let's compare this line to
rectangles and inches we can see that the line is seven rectangles long and
when we measure it in inches we see the line is five inches long so what can we
say about the rectangles are they longer or shorter than one inch yeah that's
right each box is shorter than one inch let's talk about inches in the real
world inches aren't very big in fact your thumb is about two inches long what
types of things make sense to measure in inches we can measure leaves from trees
and inches this one is eight inches long and we can measure fruit like bananas
this one is 11 inches long as a general rule we use inches to measure things
that are between the length of your thumb and the length of a banana great
job learning all about inches now practice what
learned by doing the online games and quizzes have fun and remember to always
be clever