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Students will determine what mistake this calculator is making when multiplying.
First, students will identify the mistake in a faulty calculator’s multiplication answers and write down their ideas.
Next, students will predict the results of three multiplication problems using a broken calculator that only multiplies digits.
Finally, students checked their multiplication predictions using a broken calculator that provided incorrect answers for various math problems.
Students will determine what mistake this calculator is making when adding.
First, students will identify the repeated mistakes made by a calculator when adding numbers.
Next, students will predict the incorrect results for three addition problems.
Finally, we reveal the answers.
Students determine the error in these subtraction problems.
Students analyze three incorrect subtraction problems and explain the error.
Then, using the error, they answer how the broken calculator would do it.
We reveal the answers to the final three problems.
In these math problems, the solution is already given. But another number is missing!
Practice math fluency with this dice-based calculation game.
Learn the basic rules of Contig.
Now, let’s think about how to spice it up!
Sets of multiplication and division practice problems. But the unknown isn’t where you expect it to be!
Four sets of 2-digit and 3-digit addition and subtraction practice. But the unknown isn’t where you expect it to be!
Students will quickly recognize whether a number is divisible by 3 or 5 (or both!).
Students will learn this numerical grid-based math game.
Students will analyze partially complete, multi-digit addition problems and find as many solutions as possible.
Students will analyze partially complete, multi-digit subtraction problems and find multiple solutions that complete the problems.
Students will explore the rules of how adding and subtracting evens and odds leads to either evens or odds. They’ll try to explain the why and also answer the question: which has more power, evens or odds?
Students explain why adding two evens always leads to an even.
Students find the rules for even+odd, odd+even, and odd+odd and attempt to explain why these are rules.
They do the same for subtraction: what happens when we subtract even-even, even-odd, odd-even, and odd-odd? Why?
Finally, your students will consider, after all this, which has more power: evens or odds?
Students learn to group numbers by increasingly large groups of ten rather than going to hundreds or thousands.
Students decide how they’ll read 340, 621, 835, and 999 if there were no “hundreds” place.
Students predict how to read 999 + 1.
Students predict how to read 9999 and 10000.
Students learn that in other cultures, people do indeed group their larger numbers differently.
Students will estimate the number of parking spots in Disneyland’s parking structure and then calculate how much money the structure brings in each year.
Students create three guesses: too high, too low, and a reasonable guess. This is a low-anxiety starting point that anyone can attempt.
Using a high-contrast version of the photo, students generate a few strategies for estimating the number of spots. They will note the potential inaccuracies with each strategy.
Upon learning that the structure has six levels, students will revise their best estimate.
Students learn the real answer and then attempt to calculate how much money the parking structure brings in per year.
After learning the real answer, students are left with a final question: how many people park in the lot. And how much money do they generate in ticket sales?
Students will find multiple solutions to a single math statement by filling in the blanks.
First, students look for as many possible solutions as they can find.
Then, they look for patterns in their findings and give each pattern a name.
Finally, which of those patterns would hold true if we changed from subtraction to addition on the right side of the equation?
Students will find multiple solutions to a single math statement by filling in the blanks.
First, students look for as many possible solutions as they can find.
Then, they look for which digits don’t appear in any solutions and explain why those digits don’t work.
I explain why 0, 5, and 7 don’t appear in any solutions.
Students will find multiple solutions to a single math statement by filling in the blanks.
First, students look for as many possible solutions as they can find.
Next, they look for the largest possible exponent that will work.
I explain my findings.
Students will find multiple solutions to a single math statement by filling in the blanks.
First, students look for as many possible solutions as they can find.
Then they explain why there are so few odd numbers in the dividend of the solutions.
I explain the main reasons why there are so few odds.
In this video, we’ll investigate how to round to numbers other than multiples of ten. Sure, we could round 16 to the nearest ten, but what if we wanted to round 16 to the nearest 9? Or 12, 52, or 75? We take the routine math skill of rounding and force students to truly think about why a number rounds up or down.
Round 15 to the nearest 9. Should it round up to 18 or down to 9?
Create a rule for rounding up to the next 9. Round three more numbers to the nearest 9.
Create a rule for rounding up to the next 7, 15, and 18.
See how to expand this rule to round to any number.
To help students understand place value, we venture beyond our typical decimal number system and explore a Base 9 system. Students will be exposed to ancient Babylon’s Base 60 system and computers Binary and Hexadecimal before creating their own number system.
Students consider what a “numeral” is and just how many we actually use.
We discuss our ten numerals and how the base 10, or decimal, system works. Then we introduce base 9, pondering what 8 + 1 would equal in a system without a symbol for 9.
We dig further into Base 9, asking students to complete a worksheet transforming base 9 numbers into base 10.
After correcting the worksheet, we explore real world number systems: Babylonian, Binary, and Hexadecimal. Finally, students develop their own, non-base-10 system and create two-digit numbers using this worksheet.
Students will develop a winning strategy for this simple math game.
Students learn the rules of the game.
Then, they develop a strategy guide.