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G'day, I'm Dr Peter Price of Classroom Professor. Welcome to this video in my Free Math Worksheets
Series. The worksheets this week come from this eBook; it's a book accompanying our software,
"Classroom Professor Gadgets" and the book is called "Number Facts", because that's one
of the gadgets if you look on the cover, you can see a picture of the software, it's basically
got a number fact grid in the middle and a number of tools that you can use to investigate
the number facts. So, not our usual set of worksheets so this is not simply to develop
fluency as such with number facts but to explore the patterns in the number fact, so it's a
supplement to the other sets of worksheets that I normally talk about, to help students
to more thoroughly understand the number facts and to investigate what they can see in them,
which is what the software is for. So this particular set of worksheets we're calling
"Number Fact Families, A, B, C and D in Multiplication". Now it's actually multiplication and division
and because we're starting form A, we've got harder one to go on beyond that, but we start
with the easiest multipliers and then we move on, so we've got x2, x5 and x10, x3 and x4.
Ok, so "What do we mean by number fact families?" quite simply we want the students to see that
when they know one number fact and they know it really well, there's a cluster of four
number facts usually, two, well I should talk about that in a minute, but there's generally
a cluster of four number facts that go together, that belong together, as Sesame Street use
to say, they're in a sort of "Family" because they use same name numbers, so here's an example,
"2 x 7 = 14" "What associated number facts are there for that example, children?" Well
if we're going to reuse the same numbers, the answer's not that difficult, we can do
another multiplication fact, that we can call, a "Turn around Fact" the technical name is
its "Commutative", the operation is commutative, I use to get all those terms mixed up but
I've realised that commutative is a bit like "Commuting", if you commute to work, you go
backwards and forwards, commutative rule/principle is you can turn the two of them around, 2:7,
7:2 same thing it's commutative. Ok, so that's another one, then we've got two other facts,
if we start with the 14 and divide, again we've got two examples, "14 / 2 = 7, 14 / 7
= 2". So there is our cluster or family of number facts and notice, you only have, effectively
you only have to learn one of those and you know the other three, so if you focus your
attention on this as a group of number facts, I think you are being efficient, you know
you're being strategic about learning the number facts, you're certainly not using an
old fashioned "Rote method", I don't know if you remember doing rote methods at school,
but I do, and we would go, "2 ones a 2, 2 ones a 2, 2 twos a 4, 2 twos a 4, 2 threes.."
even the easy ones we just keep repeating them, and the hard ones we just them once
or twice each, "2 sixes a 12, 2 sixes a 12, 2 sevens a 14, 2 sevens a 14, 2 eights a 16..."
if you do that long enough you will learn your number facts, however, if you forget
one, you probably have to go all the way through the whole sequence before you can find it,
that's actually the problem with singing the number facts, you may come across this idea
that if we put it all to music, then children will learn it because learning a song is relatively
easy, yes they will learn it, yes they will learn the song, but is they forget one part
way through the song they'll have to sing the whole rotten song before they get to it.
Alright, so if you were learning the 2x number facts and you knew 2 sevens a 14 using that
method you might not even think about 7 twos a 14 and you would never get down to the dividing
by 2 and dividing by 7 as well, this is as I've said a more strategic approach, so I'll
focus on this four number facts together, and the worksheets as you'll see will show
the students, well early on we have all four of them, but without the right hand side,
the answers as it were and they just have to be filled in, and then later on we just
give the students one or two of the number facts and they figure out the rest and you
know fill them in as families of number facts. So as I've said it's a strategic approach,
it's a way to help the students think about the fact that perhaps they know more than
they thought they did, you know, or that they can reuse knowledge, you know the idea that
you can take something meant for one purpose and repurpose it, it means you don't have
to create everything again, it's a bit like you know, if you're writing any sort of word
document generally you've got one you did before, that you can reuse, and repurpose
it and just change little bits, it's very much like that, if you already know 2 sevens
a 14, then you should know 7 twos a 14, and you should know the divisions that go with
it, and so on. Ok, that's the end of this video, you might recognise that I've started
doing this videos in sets, cause I'm wearing the same shirt and tie week after week, this
is the last one of this set, we're not up to 66 weekly sets of worksheets, I do hope
that you enjoy them, I'd love to hear your feedback, so now is a good point of time for
me to stop for a moment and say, please leave me some feedback, give me a comment, send
me an email, find us on Facebook, whatever you'd like to do, but I'd really like to hear
how you're find the videos and the worksheets, let me know if you've got some topics you'd
like see covered and I'd just love to hear from you. That's it for this week; I look
forward to talking to you next time.