Skip to Content

Using Math to Create the Star Wars Galaxy {with free printable!}

Enjoy this FREE printable Star Wars math activity (and sneak in some learning) while you celebrate Star Wars Day on May the 4th (be with you!)

In addition to being Star Wars fans, we also love cool STEM activities that are related to favorite movies.

And that’s exactly what I told my daughter when I suggested today’s activity —


Star Wars Planets Math Game with free printable

Star Wars Planets Math Game

When she got home from school one afternoon, I said:

Me:  “Hey, do you want to do a cool Star Wars activity?”

Kid:  “YES!”  She’s a fan girl.

Me:  “Ok, grab the calculator and meet me outside.

Kid:  “Yea!  Hey wait, does that mean you’re trying to trick me into doing some math?

Ah, the force is strong in this one 🙂

So yes, I fully admit to sneaking math into fun activities 🙂

Actually, I fully admit to sneaking learning into ANY activity (but in my defense, everyone always a great time).

Like our Plotting Points at the Park Math Game, this activity is for older kids OR kids who really love math!

The idea behind our Star Wars adventure was to actually introduce some advanced math concepts to a kid who’s not so crazy over math 🙂

See more of our recommended Math Books for kids who love to read but don’t like math!


Connecting Star Wars and STEM Activities

The goal:  Create a Star Wars Galaxy using these free printable planet labels and a variety of sports balls

The challenge:  Use math calculations to make a Scale Model of the Star Wars planets — meaning that we need to know the size of each planet and keep the same size relationship when choosing which sports ball to use for each one.

One thing I LOVE about this activity is that there are SO many math terms that come about in a natural way (you’ll totally see what I mean).  We’re also including the resources we used along with affiiate links for the books & items you may need for the project.


Star Wars Planets Math Game with free printable


First up — you’re going to need these 2 free Star Wars printables — the Star Wars Planet names & Worksheet below!   (I love making free things for you guys 🙂

The second page of the printable includes the Planet labels for each one in the Star Wars Galaxy as seen above. 

We cut out each of the planet labels and taped them to popsicle sticks because we wanted to create our galaxy in the backyard (so the popsicle sticks helped us to stand the signs up in front of each sports ball).


Star Wars Planets Math Game with free printable

The first page of the free printable is the math calcuation worksheet you see above — we’ve filled in the current size of each of the planets to give everyone a head start.

You can see on the sheet, the kids will need to do two sets of calcuations:

1. If you choose, ask your kids to convert the metric size of each planet to the standard measure

You’ll be converting from kilometers to miles so you want to multiple the current size by .62 to get the planet’s size in miles.  We chose to do this because we were using a measuring tape and my daughter is much more familiar with standard measure.  Plus, I think conversions are great because they help kids become more familiar with both measurement systems.


2.  Next, you’ll want to convert from miles to inches.

This can be done many ways depending on how big or small you’d like your scale model to be once finished.
For our model, we wanted the planet sizes to be somewhere between 3 inches and 16 inches based on the sports balls we rounded up to use so we decided to divide each planet size by 1000 and then use a 1:1 conversion from miles to inches.

What you need to know about a scale model — as long as you use the same math calcuations with ALL of the items in your set, you are scaling everything down equally and keeping the same size relationship between the planets.

Here’s an example:  Tatoonie was 6499 miles in diameter so we divided by 1000 to get 6.5 miles and then just converted it to inches so it would be 6.5 inches.  Then we did the same thing for all the other planets.

You can see that in addition to the calculator, we also have a ruler and a flexible Tape Measure in the photo — I’ll tell you more about those in a few minutes.


 Star Wars Planets Math Game with free printable

So hand the kids a Calculator and let them get going!

And yes, calculator skills are good for exercises like this — kids use them in school so it’s nice to give them some opportunities are home to understand when they should use a calculator and when they can really rely on their mental math skills.


Star Wars Planets Math Game with free printable

Next, round up as many sports balls or round objects to use as planets. 

On the worksheet, we calculate the diameter of each planet so a circular object or sphere would have a diameter (which is measured when you have a straight line going through the center of the sphere).

Ok, we have our measurements & our sports balls — time to measure the diameter.

So ask the kids how they will do that — and I’m sure they will grab the ruler and try to measure AROUND the ball.


Remember when I said math terms would come up in the discussion?!

Here’s where we remind them that the measurement around the ball is the CIRCUMFERENCE of the circle or sphere. 

So next question:  Can you measure the diamter of a 3D object?

Nope — you can’t put the ruler through the ball.

Now you have two choices —

• For younger kids, you can use the measurements in your last column as the circumference measurment instead of the diameter.  Remember the idea for a scale model, as long as you use the same calculations with all of your items, you are keeping the same relationship. 

• The second option is to calculate the circumference of each planet. 

This can be done by using the forumla: Circumference = 3.14 x diameter

Obvioulsy this is much more advanced math and if you have high school kids, this is a great opportunity to have them work with pi (3.14)



We always love to link books with our activities especially things like math concepts — here’s a few that we love:

The Librarian Who Measured the Earth is a great book about the Greek philosopher and scientist Eratosthenes who accurately measured the Earth’s circumference.

Sir Cumference and the First Round Table (A Math Adventure) is the first in an awesome math series!  This story features a fun way to learn about radius, diameter and circumference.  I highly recommend the Sir Cumference books for kids who love to read but aren’t crazy about math.


Star Wars Planets Math Game with free printable

We went the first option and began calculating the circumference of the various sports balls we had gathered. 

This is where a flexible Tape Measure comes in really handy!  I have one in my sewing kit so you might check there if you or someone at your home does any sewing.


Star Wars Planets Math Game with free printable

 As we found balls that fit our planet size, we would set them in the yard next to their planet sign.


Star Wars Planets Math Game with free printable

We decided to line them up to get an idea of their size relationship to one another — that HUGE green yoga ball is Yavin Prime!


Star Wars Planets Math Game with free printable

Then we grouped them a little closer to get an idea of scale — most of the planets we remember from Star Wars: A New Hope  are pretty similiar in size.  Hoth, Dagobah, Tatooine and Alderaan were dwarfed by Yavin Prime.

Ultimately, kids will be able to see which planets are about the same size vs which are mega planets — and also great a really good grip on how scale models can work.



Get the FREE printable set of Star Wars math worksheets & build your own galaxy!


More Fun Math Activities:

10 Math Books & Measurement Tools

Popcorn Math & Science Activities

15 Animal Math Activities for Preschool & Early Elementary