MathCounts: Grandfather Clause for Existing Homeschool Teams

Posted on by Denise Gaskins

Click here for the official update. Small schools are not mentioned, but it seems logical that their existing teams would also be grandfathered in. Maybe? and according to Mathmom’s comment below, small schools are left out in the cold.

… After taking all concerns into account, a compromise was crafted that would grandfather in homeschools and virtual schools that participated in the 2009-2010 program year to allow them to participate on teams in this year’s Competition Program. All new homeschool and virtual school participants must abide by the new eligibility rules that require those participants to register only as individuals. This compromise was brought to the MATHCOUNTS Board of Directors and approved unanimously.

Therefore, for the 2010-2011 school year, all homeschool and virtual school groups that registered for the MATHCOUNTS Competition Program either as teams OR individuals during the 2009-2010 program year will be allowed to register teams or as individuals for the upcoming 2010-2011 program year, following all of the 2009-2010 requirements for participation.

MathCounts: No More Homeschool Teams

Posted on by Denise Gaskins

MATHCOUNTSIf you’ve heard rumors about the new ruling, here is the official take.

I try to avoid ranting on this blog, but I’m deeply disappointed. My students always enjoyed the team aspect of working/suffering together. I don’t know if any of them will be willing to participate as individuals.

Update: MathCounts: Grandfather Clause for Existing Homeschool Teams

How to Start an Argument: The Monty Hall Problem

Posted on by Denise Gaskins


[Photo by MontyPython.]

You can get a good argument going in almost any group of people with the infamous Monty Hall problem:

Imagine you are on a TV game show, and the host lets you choose between three closed doors. One of the doors hides a fancy sports car, and if you pick that door, you win the car.

You pick door #1.

The host opens door #3 to reveal a goat. Then he gives you a chance to switch your door for the unopened door #2.

Should you switch?

What if you say you’re going to switch, and then the host offers to give you $5,000 instead of whatever is behind door #2?

Try the game for yourself at the Stay or Switch website.

Continue reading How to Start an Argument: The Monty Hall Problem

Probability and Baby Blues

Posted on by Denise Gaskins


[Photo by audi_insperation.]

[In The Birthday Surprise, Alex discovered her family was expecting a new member…]

What will the baby look like, Alex wondered. “Dad, is there any way to tell whether the baby will have blue eyes like I do, or brown like the rest of the family?”

Dr. Jones shuffled the papers on his desk and found a blank page. “Over 100 years ago, the Austrian monk Gregor Mendel studied genetics, or how various traits are passed down from one generation to another.” He began to draw a diagram as he talked.

Continue reading Probability and Baby Blues

Rate Puzzle: How Fast Does She Read?

Posted on by Denise Gaskins


[Photo by Arwen Abendstern.]

If a girl and a half
can read a book and a half
in a day and a half,
then how many books can one girl read in the month of June?

Kitten reads voraciously, but she decided to skip our library’s summer reading program this year. The Border’s Double-Dog Dare Program was a lot less hassle and had a better prize: a free book! Of course, it didn’t take her all summer to finish 10 books.

How fast does Kitten read?

Continue reading Rate Puzzle: How Fast Does She Read?

Hobbit Math: Elementary Problem Solving 5th Grade

Posted on by Denise Gaskins

[Photo by OliBac. Visit OliBac’s photostream for more.]

The elementary grades 1-4 laid the foundations, the basics of arithmetic: addition, subtraction, multiplication, division, and fractions. In grade 5, students are expected to master most aspects of fraction math and begin working with the rest of the Math Monsters: decimals, ratios, and percents (all of which are specialized fractions).

Word problems grow ever more complex as well, and learning to explain (justify) multi-step solutions becomes a first step toward writing proofs.

This installment of my elementary problem solving series is based on the Singapore Primary Mathematics, Level 5A. For your reading pleasure, I have translated the problems into the world of J.R.R. Tolkien’s classic, The Hobbit.

UPDATE: Problems have been genericized to avoid copyright issues.

Continue reading Hobbit Math: Elementary Problem Solving 5th Grade

Review: Math Mammoth

Posted on by Denise Gaskins

When Maria of Homeschool Math Blog asked if I would review her Math Mammoth curriculum, I jumped at the chance. I’ve always enjoyed her blog posts, and I liked the worksheets I had seen on her website. (Maria gives away more than 300 pages absolutely free!)

She sent me her then-new 4th grade worktexts, and Kitten and I dug in.

Well, that was longer ago than I care to admit. But of course, it takes quite a bit of daily use before one can be absolutely sure of one’s opinion about a homeschool program — or at least, it does for me. Too many times a homeschool resource will look great in the catalog, and we’ll start it with high hopes only to bog down in the day-to-day grind and abandon it after a few weeks or months. So I wanted to give Math Mammoth a thorough workout before I wrote this review.

And all excuses aside, I really am a pro at crastinating…

My aim is to help parents and teachers teach math so our children and students can really understand what is going on. I’ve strived to explain the concepts so that both the teacher and the student can “get it” by reading the explanations in the books.

— Maria Miller
author of Math Mammoth worktexts
and Homeschool Math Blog

Continue reading Review: Math Mammoth

Game: Target Number (or 24)

Posted on by Denise Gaskins

[Photo by stevendepolo via Flickr (CC BY 2.0).]

Math concepts: addition, subtraction, multiplication, division, powers and roots, factorial, mental math, multi-step thinking
Number of players: any number
Equipment: deck of math cards, pencils and scratch paper, timer (optional)

Set Up

All players must agree on a Target Number for the game. Try to choose a number that has several factors, which means there will be a variety of ways to make it. Traditionally, I start my math club students with a target of 24.

Shuffle the deck, and deal four cards face down to each player. (For larger target numbers, such as 48 or 100, deal five or six cards to each player.) The players must leave the cards face down until everyone is ready. Set the remainder of the deck to one side.

Continue reading Game: Target Number (or 24)

Prime Numbers Are like Monkeys

Posted on by Denise Gaskins

[Photo by mape_s.]

I’m afraid that Math Club may have fallen victim to the economy, which is worse in our town than in the nation in general. Homeschooling families have tight budgets even in the best of times, and now they seem to be cutting back all non-essentials. I assumed that last semester’s students would return, but I should have asked for an RSVP.

Still, Kitten and I had a fun time together. We played four rounds of Tens Concentration, since I had spread out cards on the tables in the library meeting room before we realized that no one was coming. Had to pick up the cards one way or another, so we figured we might as well enjoy them! She won the first two rounds, which put her in a good mood for our lesson.

I had written “Prime numbers are like monkeys!” on the whiteboard, and Kitten asked me what that meant. That was all the encouragement I needed to launch into my planned lesson, despite the frustrating dearth of students. The idea is taken from Danica McKellar’s book Math Doesn’t Suck.

Continue reading Prime Numbers Are like Monkeys