Arithmetic (all content)
Learn arithmetic—addition & subtraction, multiplication & division, fractions, decimals, and more.
6 units307 videos22 hours
Learn it live with a class on Puzzicle · Teachers: use it with your class
Unit 1: Place value
Ones and tens
Comparing 2-digit numbers
Regroup whole numbers
Comparing 3-digit numbers
Rounding
Intro to place value
Finding place value ✓ Check-ins2:25
Use place value blocks to show numbers within 1,000 ✓ Check-ins4:21
Place value tables within 1,000 ✓ Check-ins2:31
Identifying value in digits ✓ Check-ins2:42
Creating the largest number ✓ Check-ins2:18
Place value blocks ✓ Check-ins5:40
Place value: comparing same digit in different places ✓ Check-ins2:40
How 10 relates to place value
Ways to write whole numbers (expanded form and written form)
Regrouping whole numbers
Comparing multi-digit numbers
Rounding whole numbers
Unit 2: Addition and subtraction
Basic addition and subtraction
Addition and subtraction word problems within 10
Addition and subtraction within 20
Adding within 20 using place value blocks ✓ Check-ins1:24
Adding within 20 using ten frames ✓ Check-ins2:38
Adding 7 + 6 ✓ Check-ins3:53
Adding 8 + 7 ✓ Check-ins3:19
Adding with arrays ✓ Check-ins1:54
Subtracting different ways ✓ Check-ins12:32
Subtract within 20 using a number line ✓ Check-ins1:20
Subtract within 20 using place value blocks ✓ Check-ins1:19
Subtract within 20 using ten frames ✓ Check-ins0:56
Subtracting 14 - 6 ✓ Check-ins4:03
Word problems within 20
Word problems with "more" and "fewer"
Intro to addition with 2-digit numbers
Intro to subtraction with 2-digit numbers
Strategies for adding and subtracting within 100
Addition within 100
Subtraction within 100
Word problems within 100
Adding and subtracting on number line word problems ✓ Check-ins4:27
Adding two digit numbers on a number line ✓ Check-ins3:36
Subtraction word problem: tennis balls ✓ Check-ins3:33
Addition word problem: horses ✓ Check-ins3:31
Subtraction word problem: snow ✓ Check-ins4:19
Subtraction word problem: crayons ✓ Check-ins4:25
Multi step addition word problem ✓ Check-ins4:11
Multi-step subtraction word problem ✓ Check-ins4:17
Adding 1s, 10s, and 100s
Subtracting 1s, 10s, and 100s
Strategies for adding 2- and 3-digit numbers
Addition with regrouping within 1000
Subtraction with regrouping within 1000
Worked example: Subtracting 3-digit numbers (regrouping) ✓ Check-ins2:47
Worked example: Subtracting 3-digit numbers (regrouping twice) ✓ Check-ins3:48
Worked example: Subtracting 3-digit numbers (regrouping from 0) ✓ Check-ins2:24
Subtracting in your head (no regrouping) ✓ Check-ins ✎ Fixed a slip2:37
Addition and subtraction missing value problems
Addition and subtraction greater than 1000
Relate place value to standard algorithm for multi-digit addition ✓ Check-ins6:22
Multi-digit addition with regrouping ✓ Check-ins ✎ Fixed a slip8:49
Multi-digit subtraction with regrouping: 6798-3359 ✓ Check-ins3:45
Multi-digit subtraction with regrouping: 7329-6278 ✓ Check-ins4:28
Multi-digit subtraction with regrouping twice ✓ Check-ins5:06
Alternate mental subtraction method ✓ Check-ins ✎ Fixed a slip5:10
Adding multi-digit numbers: 48,029+233,930 ✓ Check-ins2:18
Relate place value to standard algorithm for multi-digit subtraction ✓ Check-ins6:38
Multi-digit subtraction: 389,002-76,151 ✓ Check-ins3:21
Unit 3: Multiplication and division
Multiplication intro
Multiplication facts
Properties of multiplication
Multiplying by tens
Multiplication by 10s, 100s, and 1000s
Multiplication: place value and area models
Using area model and properties to multiply ✓ Check-ins6:31
Multiplying with distributive property ✓ Check-ins6:58
Multiplying with area model: 6 x 7981 ✓ Check-ins3:34
Multiplying with area model: 78 x 65 ✓ Check-ins4:58
Lattice multiplication ✓ Check-ins7:15
Why lattice multiplication works ✓ Check-ins8:21
Multi-digit multiplication
Multiplying 2-digit by 1-digit ✓ Check-ins1:51
Multiplying 3-digit by 1-digit ✓ Check-ins1:54
Multiplying 3-digit by 1-digit (regrouping) ✓ Check-ins2:15
Multiplying 4-digit by 1-digit (regrouping) ✓ Check-ins ✎ Fixed a slip3:24
Multiplying 2-digit numbers ✓ Check-ins4:07
Multiplying 2-digit by 2-digit: 36x23 ✓ Check-ins ✎ Fixed a slip11:15
Multiplying 2-digit by 2-digit: 23x44 ✓ Check-ins3:18
Multiplying multi-digit numbers ✓ Check-ins10:27
Relating multiplication and division
Division intro
Division problems that work out nicely
Division: place value and area
Multi-digit division (no remainders)
Remainders
Multi-digit division (remainders)
Intro to long division (remainders) ✓ Check-ins ✎ Fixed a slip11:39
Dividing by 2-digits: 6250÷25 ✓ Check-ins ✎ Fixed a slip9:35
Dividing by 2-digits: 9815÷65 ✓ Check-ins5:09
Dividing by 2-digits: 7182÷42 ✓ Check-ins2:49
Partial quotient method of division: introduction ✓ Check-ins ✎ Fixed a slip8:27
Partial quotient method of division: example using very large numbers ✓ Check-ins7:56
Multiplication and division word problems
Unit 4: Negative numbers
Intro to negative numbers
Number opposites
Absolute value
Intro to adding negative numbers
Intro to subtracting negative numbers
Adding & subtracting negative numbers
Adding & subtracting with negatives on the number line
Multiplying & dividing negative numbers
Multiplying positive & negative numbers ✓ Check-ins5:34
Multiplying numbers with different signs ✓ Check-ins2:26
Why a negative times a negative makes sense ✓ Check-ins6:14
Dividing positive and negative numbers ✓ Check-ins4:52
Multiplying and dividing negative numbers ✓ Check-ins ✎ Fixed a slip8:30
Why a negative times a negative is a positive ✓ Check-ins5:47
Simplifying complex fractions ✓ Check-ins ✎ Fixed a slip5:19
Unit 5: Fractions
Fractions intro
What fractions mean
Fractions on the number line
Fractions and whole numbers
Comparing fractions
Comparing fractions with > and < symbols ✓ Check-ins5:19
Comparing fractions with like numerators and denominators ✓ Check-ins4:48
Comparing fractions ✓ Check-ins2:30
Comparing fractions 2 (unlike denominators) ✓ Check-ins7:08
Comparing and ordering fractions ✓ Check-ins ✎ Fixed a slip7:48
Ordering fractions ✓ Check-ins5:59
Equivalent fractions 1
Equivalent fractions on the number line
Equivalent fractions 2
Common denominators
Decomposing fractions
Adding and subtracting fractions with like denominators
Mixed numbers
Adding and subtracting mixed numbers
Visually adding and subtracting fractions with unlike denominators
Adding and subtracting fractions with unlike denominators
Adding and subtracting mixed number with unlike denominators
Adding and subtracting fractions with unlike denominators word problems
Multiplying unit fractions and whole numbers
Multiplying whole numbers and fractions
Multiplication as scaling
Multiplying fractions
Intro to multiplying 2 fractions ✓ Check-ins5:06
Multiplying 2 fractions: fraction model ✓ Check-ins4:57
Multiplying 2 fractions: number line ✓ Check-ins4:46
Multiplying 2 fractions: 5/6 x 2/3 ✓ Check-ins2:26
Finding area with fractional sides 1 ✓ Check-ins3:47
Finding area with fractional sides 2 ✓ Check-ins7:02
Multiplying mixed numbers
Multiplying fractions word problems
Fractions as division
Dividing fractions by fractions
Dividing fractions word problems
Unit 6: Decimals
Intro to decimals
Decimal place value intro
Decimals on the number line
Rewriting decimals as fractions
Adding decimals: standard algorithm
Subtracting decimals
Subtracting decimals: standard algorithm
Adding and subtracting decimals word problems
Multiplying decimals
Multiplying decimals: standard algorithm
Dividing decimals
Dividing decimals: standard algorithm
Learn this with a class
With a class on Puzzicle this course runs as a timetable of live study parties: your batch watches together and answers the check-ins, sometimes with a teacher leading.
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