February 16, 2015

An easy lesson on square roots

I've posted on my site a beginner video lesson on square roots. You can also watch it below:
Finding a square root of a number is like finding the side of a square when the area is known. Square root symbol acts as a grouping symbol: anything under it is in parentheses and is solved first. I also solve a few problems involving area & perimeter of squares.

I hope it's helpful!

February 13, 2015

Puzzle corner was too easy!

One of my customers mentioned that this particular puzzle corner from Math Mammoth Grade 1-A was too easy for her son:

Puzzling math problems

I admit, it's kind of easy. But, like I told her, I'm sure some children enjoy having an easier puzzle corner in between the others because several people have mentioned they are challenging to their children.

But, you can make it more challenging very easily: simply add a number to each equation... and possibly also make (some of) the numbers bigger. Check the examples at



February 07, 2015

Ratios & Proportions book has been updated!

Math Mammoth Ratios, Proportions & Problem Solving math book cover Math Mammoth Ratios, Proportions & Problem Solving is a worktext that concentrates, first of all, on two important concepts: ratios and proportions, and then on problem solving. It is meant for grades 6-7.

This book has been now updated to include many new lessons that will ALSO be in the upcoming Math Mammoth grade 7-B. This means that you can use it to continue pre-algebra studies after finishing 7-A.

See free samples and more info:


For now, I've kept the download price at $5.00 though the book became quite a bit longer.

January 29, 2015

Math worksheets in PDF form

Time to celebrate!

I've been working hard on the various worksheet generators at HomeschoolMath.net, and now all of them make worksheets both in PDF and html formats!

Below you can see examples of the variety of the worksheets:

The advantage of the PDF format is that it's portable and you'll instantly see how it prints.

The advantage of the html format is that you can edit it! Simply save the worksheet to your device and then open the file in a word processing software.

The worksheets cover topics from grade 1 through pre-algebra, such as: all the basic operations, clock, money, measuring, fractions, decimals, percents, proportions, ratios, factoring, equations, expressions, graphing, geometry, square roots, and more. And it's all free. Enjoy!

January 22, 2015

Happy Face Math

Image credit Charlie Smith

Some pointers/explanations in case you find these cryptic:

A happy face to the power of -1 is the inverse of happy face.
Happy face squared or cubed are pretty easy.
"sup" in mathematics is the supremum of a set.
Then we have a partial derivative of Happy Face.
Next, sine of Happy Face = Happy Face sign by the road.

In the second column, Re( :) ) is the real part of Happy Face, which is Happy Face without the eyes (without i's).
Im of Happy Face is the imaginary part of Happy Face = the eyes (the i's).
[Note, i is the imaginary unit used with imaginary numbers.]

Triangle followed by X is the mathematical operation curl (of a vector).
Next, the upside-down triangle is the gradient of Happy Face or "grad" of Happy Face.
Lastly, Log or logarithm of Happy Face

January 19, 2015

Homeschool Buyers Co-op group buy for Math Mammoth

Homeschool Buyers Co-op

Homeschool Buyers Co-op is running a GROUP BUY for large Math Mammoth bundles at 40% discount – just for one week!

The offer expires on January 26, 2015.

January 15, 2015

Math Mammoth January 2015 sale!

From now till January 31, get 25% off of all Math Mammoth & Make It Real Learning downloads & CDs at Kagi store!

Use the coupon code MAMMOTH at the order page at Kagi.

At MathMammoth.com you can learn about the different books I sell and see samples.
You will find links to Kagi's order pages on my site, on the various product pages.

Or, if you are ready to order, you can use these direct links to the order pages:

Remember also, I am always ready to help you find the best book/product for your situation. For many people, a good starting point is to administer the assessment test(s). I will evaluate the results for free!

Maria Miller

January 13, 2015

Math Mammoth printed books sale

Math Mammoth printed books are on sale at Rainbow Resource Center starting today and running through January 19, 2015. The discount is 20%.

January 10, 2015

How should students show their work for math word problems?

Someone recently asked me about showing work in math word problems and I thought others might enjoy hearing about this topic also.

Personally, in the lower grades, I'd ask the child to EXPLAIN their thought processes orally, and then gradually teach them to write something on paper. The main thing students in grades 1-3 need to write is the actual calculations they did, not only the final answer.

For example, if they added 23 and 87 to get the answer, they should write 23 + 87 = 110 and include the units of whatever it was, such as $23 + $87 = $110 or 23 cm + 87 cm = 110 cm.

In the upper elementary grades (4-6) I'd like to see students write sentences and/or words in addition to the calculations so that another person can follow their solution.

I'll give some examples.

(from 4th grade)

Mr. Jefferson travels from Paducah to Lexington and back, three times a month. What is his total mileage? (A map shows that the distance in question is 255 miles.)

An example solution showing the work:

One round trip is 255 + 255 = 510 miles.
Three round trips are 510 + 510 + 510 = 1,530 miles.

(from grade 4)

Mick earned $345 from strawberry picking, and Jeanine earned three times as much. How much did they earn in total?

A concise solution showing the work:

Jeanine: 3 × $345 = $1,035
Total: $345 + $1,035 = $1,380

A bit more wordy solution showing the work:

Jeanine earned 3 × $345 = $1,035.
In total, Mick and Jeanine earned $345 + $1,035 = $1,380

Both should allow another person to follow the reasoning.

(from grade 5)

A T-shirt cost $10.50, but now it is discounted by 2/5 of its price.
Annie buys ten shirts with the discounted price. What is her total bill?

An example concise solution showing the work:

Cost of one shirt:
$10.50 ÷ 5 = $2.10
3 × $2.10 = $6.30

Total bill:
10 × $6.30 = $63.00

A bit more wordy solution:

One shirt costs 3/5 of $10.50, which is $10.50 / 5 × 3 = $6.30.
Then ten shirts cost 10 × $6.30 = $63.00.

David pays a 20% income tax on his $2,100 salary.
a. How many dollars is the tax?
b. How much money does he have left after paying the tax?

These are very simple questions so this time writing the calculations is enough.

a. $2,100 / 10 = $210
2 × $210 = $420


$2,100 / 5 = $420.

b. Again, all that's necessary to show the work is to write a subtraction.

$2,100 − $420 = $1680

(from 6th grade)

14. A herd of 40 horses had some bay, some chestnut, and some white
horses. Thirty percent of them are bay, and 45% are chestnut.
How many horses are white?

An example solution showing the work:

100% − 30% − 45% = 25%.
So 25% of the horses are white.
25% is 1/4.
And 1/4 of 40 horses is 10 horses.


Percentage of white horses:
100% − 30% − 45% = 25%
25% of 40 horses is 10 horses.
So 10 horses are white.

In a nutshell:

The purpose of writing down the work allows someone else to follow the person's thought processes. This is of course important for students to learn no matter what their future occupation: they need to be able to explain to others how they solve a problem, whether a math problem or a problem in some other field of life!

One more tip: You could ask a fellow student or sibling to read the student's work to check if it can be followed and understood!

January 08, 2015

Sale on MM printed books


Rainbow Resource will run a sale on Math Mammoth printed books from Tuesday, January 13 till Monday, January 19.

 (I don't know what the discount percentage will be).

January 04, 2015

2015 Mathematics Game is here!

Photo by Carol Vanhook
If you don't know, this is a fun game where we try to make the numbers from 1 to 100 using the digits 2, 0, 1, 5 and various math operations. For example, you could write

25 − 10 or

5 + 1 − 2 + 0 or

5 × (2 + 1 + 0) or

50 / 2 − 1

etc. and you'll get various numbers. The challenge is to make ALL of them from 1 to 100!

Take special note: square roots, exponents, and factorials are allowed.
This means you can do 52 + 10, √25 − 10, and 0! + 1 + 2 + 5. You can even use decimals, such as .2 to make 5 × .2 + 10.

You can submit your results to Math Forum.

Denise at Let's Play Math also accepts submissions. Her rules are a tiny bit different from Math Forum's. Check out both:



And have fun!