Author: Bon Crowder

  • Two Reasons to Memorize Math Facts

    Two Reasons to Memorize Math Facts

    I learned my math facts by “singing” them while looking at flashcards.

    Having these facts ingrained with chanting or singing isn’t a bad idea. It might not “feel right” because we’re so into experiential learning these days. But if a kid can’t immediately access and use things like 8 x 7 = 56, he’s going to be slower than if he can.

    And if he’s slower, he might get frustrated and start to think that he’s not good at math.

    Also, knowing these cheap and dirty math facts helps with confidence. Even if a kid’s struggling with other things in math, knowing that he has this one thing (the “facts”) will help out.

    I fight this battle often. Some people feel that math facts shouldn’t be memorized. But there’s so much value in it.

    How about you? Which side of the fence are you on?

  • Be the Village – How to Help Every Kid with Math

    Have you seen the kid that isn’t getting the attention he needs at home? Wonder what’s going to become of him?

    Well, the “it takes a village” concept isn’t far off. You might not be able to change his world, but sharing a little about math might help with one corner of it.

    Share math in small bites.

    Every time you see the child, pose a fun puzzle. It doesn’t have to be blatantly mathematical. Anything to get his logic working helps. I love the Childcraft Mathemagic book for puzzle ideas.

    Ask her random math facts. Tell her you’ll give her something for each one she gets right – or each 10 she gets right in a row. Find out what’s important to her that you can’t get in trouble sharing. Like money, chocolate, baubles, etc.

    Tell him that when you were growing up you wanted to be a mathematician. Ask him to find his favorite mathematician online. Find one yourself that you can discuss – I’m partial to Abel and Galois.

    Be positive about math.

    There might be many things wrong in a child’s life. Let math be the one that isn’t. Be positive. Help make math the thing a kid can hold on to.

    Be the village because it takes a village. Share your stories in the comments!

  • 5 Phases of Learning Math

    5 Phases of Learning Math

    This post is an answer to a question Michelle, a high school math teacher, sent. She writes:

    I explain a new concept then give an example and finally do an example with the class directing me on how to solve. What I have noticed is that the bulk of the questions occur during or after the chapter assessment. Most of the students’ questions are great questions. It’s just that the questions they are asking are ones they should have asked much earlier.

    Think of knowledge as a bag of shapes – all of which have different colors and textures. Once you get the bag, you have to sort through them. Some people want to count them, some people want to sort them by color, some by shape. Some people need to sort by texture. Some people need to sort by all three or just lay all of them out in rows to get a good look at them.

    Everyone sorts the bag of shapes differently. Likewise, everyone sorts information differently.

    Turns out, the bag of shapes isn’t the knowledge. It’s merely the information. And it takes each person “sorting” it in their own way to turn the information into knowledge.

    In teaching and learning math, I’ve noticed a cycle. I’ll use the bag of shapes to illustrate it:

    1. Exposure

    Exposure is usually in the form of lecture and examples done by the instructor. It can be the first time the student has seen it or the first time in a long while.

    This is where the student receives the closed bag of shapes.

    2. Activity

    Any activity following the exposure. This typically is in the form of homework or classwork practicing the concept and problems.

    This is the “peeking into” the bag of shapes. The student gets to remove a few of them and start looking at them.

    3. Settling

    Allowing the subconscious to work. The brain does this all on its own.

    Often mathematicians will go for long walks, go to the movies, hang out with their kids, talk to non-math people or do any number of non-math things to force the settling phase.

    Children don’t know how to force the settling phase, nor do they need to. It just happens between when they do the homework and when they start to study for the exam.

    In the bag-o-shapes analogy, this is where the students dumps all the shapes onto the floor and sorts them in various ways. It takes a while to get through all the shapes and see what kinds of sorting can be done.

    4. Re-engagement

    This is typically in the form of studying for the test and taking the test. It can be a heightened emotional situation where the learner is under stress.

    This is a revisit of the concepts. It becomes easier because the settling has occurred and the information (the bag of shapes) is already organized.

    The learner at this point will attempt to modify some of the conscious thinking to best fit with what the subconscious has done. The added stress will allow them to connect with what they’ve done better – as the “feeling” state induces a different type of learning.

    5. Application

    This is using the concepts for something else. This will often be the next class or next term of the math curriculum. If you learned graphing functions, you will likely use graphing functions in the future.

    To wrap up the analogy, this might be a student realizing that the bag of shapes is needed for something – not just a random bag of shapes. Therefore he can re-organize them to be of use in the new situation.

    Let the learning flow.

    This flow of learning is natural. It will happen and has to happen. The only thing you can do to artificially speed it up is cycle it more often.

    The students ask the good questions, as Michelle said, “during or after the chapter assessment.” This is in phase 4 – Re-engagement.

    Instead of going through a single cycle, do it two or three times. Like this:

    1. Monday: Lecture, chapter 1 (exposure)
    2. Monday: Classwork and homework, chapter 1 (activity)
    3. Friday: Test, chapter 1 (re-engagement)
    4. Monday: Lecture, chapter 2 (initial exposure to chapter 2 and application of chapter 1)
    5. Monday: Classwork and homework, chapter 2 (activity)
    6. Wednesday: Test, chapter 1 (yes – chapter ONE; re-engagement again)
    7. Friday: Test, chapter 2 (re-engagement)
    8. Monday: Lecture, chapter 3 (initial exposure to chapter 3 and application of chapters 1 and 2)
    9. Monday: Classwork and homework, chapter 3 (activity)
    10. Wednesday: Test, chapters 1 and 2 (re-engagement again)
    11. Friday: Test, chapter 3 (re-engagement)
    12. Monday: Lecture, chapter 4 (initial exposure to chapter 3 and application of chapters 1, 2 and 3)
    13. Monday: Classwork and homework, chapter 2 (activity)
    14. Wednesday: Test, chapters 1, 2 and 3 (re-engagement again)
    15. Friday: Test, chapter 4 (re-engagement)

    What do you think? Share your experiences with the cycle below in the comments.

    Thanks to Michelle for requesting this tip. Michelle is one of only two math teachers in a rural private school. She teaches Algebra I, II, Geometry and Calculus.

    Do you have a question? Ask it in the comments section.

  • How to Teach Division in the Sandbox

    How to Teach Division in the Sandbox

    Need to offer a better way to understand the concept of division and remainders? Try it in the sandbox!

    The Discovery Toys  are proportional, so they allow a really engaging way to see how division and remainders work.

    This video shows how you can help kids put together the numbers 9, 4 and 1 to “see” division at work:

    You can also do this in the bathtub or pool. And the are perfectly weighted and “massed” so they float.

    I think this has something to do with “water displacement,” but I’m not sure. I’m a mathematician, not a physicist. 🙂

  • Using Toys as Curriculum Tools to Teach Arithmetic

    Using Toys as Curriculum Tools to Teach Arithmetic

    Want to give your kiddos a jump start on multiplication and division? What to help the ones struggling with division to grasp it better?

    The Discovery Toys Measure Up Cups can do just that. They are built as a curriculum tool, in the proper ratios, so that the #6 cup holds exactly twice as much as the #3 cup. This allows for engaging and beneficial play that gives kids a grasp on how numbers relate to reality.

    For example, in this video, kids can compare the numbers 3, 6 and 9 to see how they relate:

    You don’t have to say out loud, “three plus 6 is 9” or, “9 divided by 6 is one with three left over.” But these concepts are ingrained into the child’s brain as they see this work.

    What do you think?

  • In How Many Ways Can You Solve the Thiagi Circles Jolt?

    In How Many Ways Can You Solve the Thiagi Circles Jolt?

    I was at a seminar yesterday with world famous (and awful fun) Thiagi. He keeps his participants on their toes with small activities called jolts. Jolts are defined at interactive experiential activities and:

    …force participants to re-examine their assumptions and revise their habitual practices.

    One jolt we did yesterday got me to thinking about math. Okay, many of them had me thinking about math. But this one was about the multiplication principal of counting and sets.

    The multiplication principal says that if you have 7 ways to do the first thing and 3 ways to do the 2nd thing, then you’ll have 3 * 7 = 21 ways to do them together. Assuming you pick one of each.

    So if I want a sandwich (tuna, ham or turkey) and a side (chips, onion rings, fruit or fries) for lunch, I will have the option of 3 * 4 = 12 different lunches.

    The Thiagi Circles Jolt

    Here is the Circles Jolt that Thiagi offered: Draw this figure without ever lifting your pencil or retracing over any lines (or curves):

    It isn’t hard, as you probably see. It takes anywhere from 10 to 45 seconds to figure it out. The question is, “Is there another way to do it than the one I thought of?”

    So here are the ways I immediately thought of in the Thiagi Workshop:

    The fancy pants teacher’s pet, Mark, was asked to demonstrate the answer. And he did it in an even different way! So I saw that there were 8 more ways to do it:

    Trying to trump Mark and be the new teacher’s pet, I announced that there were indeed 16 ways to accomplish Thiagi’s goal.

    And here I am. Still trying to win the favor of the teacher by producing the 16 ways via blog and video.

    There are 16 ways because of the Multiplication Principal of Counting.

    Notice there are four questions to answer when solving this:

    1. Do you start from left or right side of the drawing?
    2. Do you start by drawing the outer circle or go through and start at the inner circle?
    3. Do you go up or down on the first circle you draw?
    4. Do you go up or down on the second circle?

    Each question has two different options. So there are

    2 sides to start from * 2 circles * 2 directions to go in the 1st circle * 2 direction in the 2nd circle

    2 * 2 * 2 * 2 = 16 different ways to draw the diagram!

    Teach this with experiments.

    Although you now know how many there are, don’t teach it this way. Instead, just give the jolt to the kids. Once they solve it, show them “your way,” which should be any way that is different than theirs.

    Then tell them that for ever unique solution, you’ll give them $1. (Thiagi gave out $1 bills yesterday, too!)

    Once they come up with all 16, offer the extra $4 for some way they can show the number 16 with numbers (logically based on their solutions). They might come up with 2 * 8 or 4 * 4, as long as they can group their drawings in logical bundles.

    What do you think?

  • Teaching Patterns with Playful Bath Shapes

    Teaching Patterns with Playful Bath Shapes

    Do you get “why” questions often from kids?

    Differentiation is the foundation of learning. Curiosity comes in the form of “Why is that different?” And right behind it is “Why is that the same?”

    So patterns – and the lack of patterns – are essential in the development of a child.

    The picture below is a collection of Discovery Toys (not all of them because they live in a house with a 19mo child).

    While in the tub, I encourage Daughter to see which ones are the same color. You can label the bathtub tiles with soap crayons so you can discuss the patterns more easily. Use the Cartesian Coordinate plane or Excel cell names like I did in Photoshop.

    Here are some things to talk about to encourage pattern discovery and learning. Or click here to download this as a printable MSWord Document.

    • Which shapes are similar? Which are congruent?
    • Which shapes are kind of the same (similar, but not in the official math sense of “similar”)
    • Put shapes together that “go together” – these could be same shape, color, “feel” (like B6 and B7 are both angled).
    • Compare shape A5 to the shapes A3, A4, A6, A7 and A8.
    • What do cells B3 and B8 have in common?
    • How are C3 and C4 different?
    • What’s in common in cells A2 and B2?
    • How are shapes C1 and C2 different?
    • How are C2 and B3 similar?

    And then look at the world!

    When you’re out of the tub, make sure to encourage observations – of everything. For something like the gate trim in the picture you can ask questions like:

    • What is similar?
    • What pieces are different?
    • Do you see spots that are kind of the same but mirror imaged?
    • If you were to make this symmetric, what other parts would you have to add to it?

    Have fun. See patterns. Enjoy the discovery!

    Download the activity questions here.

  • The Only Reason to Do a Word Problem

    The Only Reason to Do a Word Problem

    I’ve avoided teaching word problems for years. Mostly because it’s hard to teach word problems.

    I’ve figured out a great way to do it, but I still don’t like it.

    I’ve learned of a thing called “What can you do with this?” from dy/dan. This teacher sets up a situation so that students can ask questions.

    I’ve been pondering the effectiveness of this for a while.

    The thought is that if you allow students to observe something interesting and ask them “What can you do with this?” then they’ll create their own word problems.

    This is in response to the fake or “made up” word problems from a textbook which mostly don’t work for teaching thinking skills.

    But the issue remains the same. If someone presents a student with a video of Coke vs. Sprite and the student lacks curiosity about that subject, then it’s still a contrived problem. Or a contrived situation.

    The only reason to do a word problem is if you’re emotionally attached to it.

    Husband and I were talking about word problems the other night. After my demonstration about using to teach math, he said he wished he learned math that way. He needed something to hold on to. A reason for doing it.

    He’s a set dresser in Hollywood for part of each year. Which means that he has to hang pictures on movie sets. And they have to be 55″ above the ground – at the center of the picture.

    Not hard to measure, but there’s also the wire on the back to consider. Is the wire dead center? No. It’s probably above the center of the picture.

    It becomes one giant word problem. But it isn’t written in a book. And it isn’t videoed by a teacher. It isn’t fake. There’s a real reason for him to do it.

    Which made me realize that there’s only one reason to do word problems: if you’re emotionally attached to it.

    If you need an answer to a question, you attach to it emotionally.

    Parent: You’ve got 45 minutes to clean the kitchen before we leave for softball practice.

    Kid: If I finish the kitchen before we leave, can I watch TV?

    Parent: Sure, but the kitchen better be spotless.

    Most likely the kid has a plan for TV – like watching his favorite cartoon on DVR that takes about 30 minutes. So he works out how fast he needs to clean the kitchen so he can get in his cartoon before leaving.

    This is a real problem. His problem.

    Watch your kids intently. See where they are doing word problems in their heads. Ask them to explain them. Give credit for work done – especially when self-created.

    If someone else needs an answer, you attach to it.

    Being helpful is a powerful motivator. Try this: with a pencil and paper sit in a public place. Act like you’re writing something important. Then ask out loud, “What’s 87 minus 13?” $5 says that at least four people will chime in to be helpful.

    Let your kid help with balancing the checkbook or creating the budget. If you’re a classroom teacher, let the kids help figure out what teacher supplies to buy. Give them a limit on what to spend and the catalog and some guidelines.

    If someone you like wants an answer, you attach to it.

    I couldn’t have given a feathery duck’s tail about biology, but the teacher was crazy cute. So I wanted to please him. So I worked. Hard. And had a 100 average.

    I suspect this is why the teacher at dy/dan is so successful. He’s cute, compelling and cool. Who wouldn’t want to engage with him?

    If you have carisma and charm, use it. This might not work as a parent but will definitely work as a classroom teacher – at least for some students.

    Give it a try. Tap into the emotion. And share your success below!

  • How to Teach Similar Triangles and Have Fun Doing It

    How to Teach Similar Triangles and Have Fun Doing It

    How about some similar triangle work on the Discovery Toys Giant Pegboard?

    Not only is this video about triangles that are similar, but this video about triangles is similar to other videos! (Is that fun to say or just annoying?)

    Here it is:

    What do you think? What other triangle things can you do with a pegboard?

  • The Difference Between Similar and Congruent Triangles

    The Difference Between Similar and Congruent Triangles

    Do your kids get confused between congruent and similar triangles? Do you?

    In a previous post, I made this mistake when discussing right triangles on the Giant Pegboard. If a mathematician can make the error, then it is easy for a kid to, also.

    In the video I said “congruent” when I meant “similar.” Two triangles are congruent if they are the same size and shape. They are similar if they are the same shape (and maybe or maybe not the same size).

    One way to show that two triangles are congruent is to use the SSS Theorem or the “side side side” theorem. This says, essentially, that…

    If you can show all three sides of two triangles are the same, then the angles must also be the same.

    This ensures that your two triangles are congruent – or as a kid might say it “exactly the same.”

    Here’s how to use the Discovery Toys Giant Pegboard to play around with congruent triangles:

    What do you think? Can you use this? Give it a shot!

    Check out the next post for a video discussion on similar triangles.