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Young, Old or In-Between… You Know You Need to Know Your Age Down to Second!


Have you ever wondered EXACTLY how old you are? Or how close you are to your next birthday? Or exactly how far apart in age you are from someone you know? Or whether your 52nd birthday is going to be on Monday or a Tuesday? Come on. You know you need to know.

These are fascinating questions, not just for kids but adults too. While you and I may be hoping our birthday is just a little further away while at the same time our kids are literally counting down the days before they get to rip open more presents, our fascination with dates is the same. We all want to know when and where the time goes and how long until we get there.

Click Here for the Age Calculator

Enter the new Age Calculator! Give it a spin and it’ll tell you the answer to all of the questions above, plus provide facts like what day of the week your birthday lands on (past, present and future), your astrological sign and more. Hover the cursor over the events in the calculator and you’ll get more details about each individual event, and you can use the arrows at the top and bottom of the display to scroll the calendar forward and backward in time to see more events.

If you make a selection in the lower part of the Age Calculator, you can look at other age-related events. Ready to settle that whole, “I’m so and so months older that you, so I know better than you…” argument definitively? Want to compare your age to a friend? Or your brother or sister? Or, (at your own risk) your spouse? Try the “Friend’s Birthday” function in the calculator and you’ll be well armed.

Curious about the next U.S. Presidential Election? The calculator will tell you when it will happen, and whether you’ll be eligible to vote or not. And, for future elections, I’ve taken a stab at a few possible candidates. I mean, up until the robots take over everything, at that point I’m not sure we get to vote anymore.

Want a quick and easy way to see how much money you need to save, and how much that money is worth in today’s dollars? The “Savings Calculator” function will let you specify an amount, investment frequency, rate of return and inflation rate. You can get a detailed breakdown of the investment over time by hovering over dates in the calendar part of the calculator, but you’ll get a ten year summary right in the age calculator’s display.

No matter what you use it for, this Age Calculator is a lot of fun to play with. I hope you’ll use it with your kids to talk about ages, birthdays, calendars and this whole passing of time thing. If you use it in your classroom, drop me a note in the comments and let me know what you did and how it worked for you, or if you just found it interesting please share it with your friends!

And all I want for Christmas is for you bloggers out there to post a link to this fun new tool! 🙂

Something New for Your Multiplication Tool Box!

Multiplication Table

My collection of multiplication charts has become one of the most popular collection of multiplication printables on the Internet, but several of you have said, “Hey Dad, where are the multiplication tables? And I haven’t had a good answer.

Until now that is!

Multiplication Table Page

Multiplication tables focus on a single set of facts, for example the times 12 multiplication table lists all of the individual facts that include 12 as one of the multiplicands. Because the facts are presented in order, they make a nice bridge between skip counting and memorization.

The multiplication table pages at the link above include versions that are suitable for reference sheets (with all of the facts solved), but there are also versions that don’t have answers (multiplication table worksheets essentially).

These multiplication tables print beautifully, and there are versions in color and B&W for each printable. You’ll find multiplication tables that have multiple fact families on them (like the multiplication table shown above), or “singles” that have exactly one multiplication table per page for a specific set of facts. Those single table pages have interesting number facts on them, which can make them a nice overview page if you’re using a “number of the week” approach to introducing multiplication facts in the classroom.

No matter how you’re tackling multiplication, I hope these help! If you like them, please consider sharing them with other teachers or parents you know via social media, or linking to the multiplication table page! Your help getting the word out there means a lot to me!

More Updates to the Amazing Fraction Calculator!

I’ve received so much positive feedback on the fraction calculator and I really appreciate everyone who’s taken the time to pass along comments and suggestions! If you haven’t had a chance to play with it, please check out the new and improved version!

Fraction Calculator with Visualizations

One thought that came up from users repeatedly was the way the previews represented mixed fractions was a little unintuitive given that the whole part of the fraction was always shown as a numeric value but the fraction had the pie-chart representation. And the concepts didn’t related particularly well to the multiplication and division operations.

To make the preview a little more useful in an instructional setting, I’ve updated it now. In general, small mixed fractions will be shown entirely as pies, with the wholes being shown as one or more complete pies divided by the numerator. If there are more than five wholes, the calculator’s representation reverts back to it’s numeric mixed fraction form.

What this accomplishes for addition and subtraction calculations is to make the representation totally visual, which is much closer to the vision I had in creating this thing.

Now multiplication and division are slightly different beasts, and in the context of the fraction calculator trying to show a meaningful visualization of how the operands translate into the product or quotient, my friend Maria Miller suggested that the right approach was really to express the multiplicands as a visualization times a number (or the dividend divided by a numeric divisor representation for division) since these operations didn’t lend themselves immediately towards the sort of counted forms that addition and subtraction do. If you think about it, this makes sense because these operations are more about repeated operations (multiples of or divisions into) a value, and the visualization of two separate fractions could almost be misleading. Either way try it out with a whole multiplicand or a whole divisor and I think you’ll find the preview is conceptually at least much better.

I still have plans to add steps the calculator is taking to generate the solutions, so for example a break down of how common denominators are determined or how the final mixed fraction might be reduced. It’s definitely a work in progress, but even now I think you’ll agree the calculator is already one of the best fraction teaching tools online!

Visual Fraction Calculator

How Prime Are You?

Prime numbers are like the Lego bricks of number theory, and if you’re a real math nerd you know you love number theory. But wading your way through a sea of composite numbers looking for those magic numbers at either end of the scale, either the noble primes themselves or those composite numbers with who have a really interesting family tree of primes that multiply out to their true quantitative majesty…

So, what every number explorer needs is a prime factorization calculator, and I just built a really fun one here. It’s animated. And in color. And perfect for playing with numbers in the classroom, on your Smart Board or just whenever you’ve got a number that seems like it’s got an interesting prime pedigree…

Prime factorizations are a great tool for figuring out greatest common divisors (or largest common denominators if that’s how you swing), or for finding the least common multiple. But naturally, this calculator will tell you quite promptly if a number is prime as well.

Give it a try and see what you can discover about your own favorite number. It’s factor tree may actually surprise you…

Prime Factorization Calculator

Return of the Timer!

Online Timer

The poor countdown timer here at DadsWorksheets has been neglected for some time, and with the site having gone through some significant technology upgrades, the timer became something of an orphan child, replete with scars and an inferiority complex, you know that one you keep in the closet and hope that at some point it’s just going to have an owl swoop in with an engraved invitation to go off to magic timer school where it saves the world or something.

After waiting somewhat impatiently for ANY sort of feathered visitor, I had to take matters more into my own hands, and a few thousand lines of JavaScript incantation later, I’m pleased to share with you the new countdown timer…

Online Countdown Timer

You don’t need to invoke specialis revelio to see this is a wizardly improvement over the old timer. Obliviously one big change is the circular timer graph, which provides immediate feedback about how far along the timer has progressed. It also lets you trigger sounds when the timer reaches the halfway mark or nears the end of the time you assign, and there are preset buttons like “Set Timer for 10 Minutes” and similar amounts that let you very quickly configure the timer for frequently used times.

As with the previous timer, you can save a URL that has all of your specific settings so that it’s easy to return to a timer ready to go.

While we’re using this as a timer for math tests and worksheets, it’s perfect for anything where you need a countdown. Use it as a classroom timer, a recipe timer or to keep track how long that pectrificus totalus is going last.

Accio Timer!

Online Fraction to Percentage Calculator

Percentage Calculator

Percentages are an important part of both math and daily life. We deal with percentages all over the place… Calculating tips, 50% off sales, sales tax, or (dare I mention it in April?) income taxes. All of these areas work with percentages.

This percentage calculator easily allows you to convert a percent to fraction or, in reverse, a fraction to percent. By playing with the various values, you can work out various types of problems (“what percent of a number is some other number” for example), and the spoken-word version of various types of problems is shown in the preview. Working various problems through the calculator will quickly build experience with various types of percentage problems.

Also be sure to check out the various fraction and percentage math worksheets on the site for more practice.

Percentage Calculator

Please Stop the Divisiveness and Start Dividing

Division Worksheets

Friends! In this era of polarized political punditry, care must indeed be taken to avoid tarnishing with undeserved negativity the very verbal tools we employ. Even supposing the differences found in our associates, our family members or our beloved (or, not so much) electoral candidates are themselves perhaps less important than they seem (or, perhaps, even more not so much), irrespective of nuance, the words we use may escalate these comparisons to Brobdingnagian proportion, and in doing so toss those loyal lexical minions into the political muck.

I loathe to say that such a fate befalls our dear associate “division” and his close kin, which in political parlance has accumulated such a dreadfully undeserved connotation. Subtraction? So negative. But division, yes, division we need by our side in its purist form. This mighty mathematical sword brings so much to our struggle for the equitable partitioning of cakes and other deserts, the proportional reduction of recipes for the making of optimistically smaller quantities of these and other tasty treats, and, importantly, the required percentage calculation of caloric reduction to target weight loss after over indulgence in what may have ultimately been a non-equitable distribution of said dessert portions.

Indeed, without division, we would all be, colloquially, fat cats.

So, take cautious heed not to bandy about words such as division or divided or divisiveness with abandon lest you too sully the reputation of this fine arithmetical specimen. Instead, share with your friends these shiny new division facts worksheets that are designed to fill an otherwise unnoticed gap in the division content on the site. They will hone your skills with basic division facts grouped by distinct divisors.

And, they’re vastly more fun than watching the primary debates.

Division Worksheets

Black Hole Date Night for Han and Leia

Han and Leia on a Date at the Black Hole

Because sometimes when you’re just hanging out with your 6th grader, the conversation drifts, and before you know it you’re talking scientific notation, gravitational mass, black holes and where Han and Leia might get to on an interesting date night… And yes, it’s so much fun to be Geek Dad.

Free Pie! And an Amazing Fraction Calculator!

Sometimes, it’s really just all about pie. Who gets how much pie. How many pieces of pie. Fractions of pies. Big fractions for me, please.

When you are learning how to add or subtract fractions, it’s easy enough to get the whole common denominator thing figured out. I mean, if Uncle Billy ate half of the cherry apple, you know you’re only going to have a third of the pie left after you take your traditional one sixth slice. Denominators of two and three and six… It’s just basic pierithmetic.

But multiplying and dividing, that requires skills. Serious skills. And that’s where this fraction calculator might come in handy. Whether you have to deal with mixed fractions or improper fractions, or if you just need a little help with the core operations on simple fractions, this calculator is built just for you. It will reduce and simply anything you put into it, and along the way give you a visual preview to help show what’s going on. Check out the YouTube video in this post for a quick demo, or just go straight to the link below.

Also works great for pizza. Because, you know. Pizza is a pie, too.

Online Fraction Calculator

Put a Little Multiplication Chart in Your Pocket!

Math Fact Bullseye Worksheets

Sometimes a letter size piece of paper is just too much, even for a 100 multiplication facts. Sometimes you just need something a little more discrete, something that you can slip into your pocket, something you can reach for on a moment’s notice without the social stigma that comes from unfurling a giant multiplication chart out of your backpack and announcing you can’t remember the product of 6×7 to the world. Again.

Well, maybe not you, but maybe one of your budding math minions.

These miniature multiplication charts are the answer! They’re laid four up to the page, ready for your local neighborhood (or supply room) paper cutter. They’re great for taping to student desktops or math notebooks or any place where a little multiplication help might be called for. Check them out, along with their full-size brethren at the link below…

Multiplication Charts

Oh, and it’s 42 by the way. Put the chart away, seriously. It’s embarrassing.

Math Worksheets