Course contents document · Elementary · generated 2026-09-14

1st Grade Math

293 core topics · approximately 87 hours of instruction including spaced review

How the course runs

An adaptive diagnostic (up to 40 questions) places the student on the course's knowledge graph - topics already known are credited, and instruction begins exactly at the learning frontier. Every topic is taught with a worked-example lesson and auto-graded practice; a topic is mastered at 75%+ and then maintained through spaced reviews on an expanding schedule. Mixed checks follow every 6 lessons; each unit ends with a 12-item quiz, and course-wide assessments appear at 25%, 50%, 75%, and 100% mastery. Prerequisite gaps below the course are detected and taught rather than skipped, so completion certifies the whole tower, not just the top.

Core curriculum

Grade 1: Addition & Subtraction to 20 · 13 topics

Counting On to Add [E] Start at a number and count forward.
Addition Within 20 [E] Sums up to 20.
Subtraction Within 20 [E] Take away to find how many are left.
Making Ten to Add [E] Break a number apart to reach a friendly 10 first.
Adding Three Numbers [E] Add three whole numbers in any order.
Fact Families [E] The same three numbers make addition and subtraction facts.
Missing Addend [M] Find the number that completes the sum.
Relating Addition & Subtraction [M] Subtraction is an unknown-addend problem.
Word Problems to 20 [M] Add or subtract to solve a short story.
True or False Equations [E] Decide whether a number sentence is true.
The Meaning of the Equal Sign [M] Equals means the two sides are the same amount.
Fluency Within 10 [E] Add and subtract within 10 quickly, from memory.
Add a Two-Digit and a One-Digit Number [E] Add ones to ones and keep the tens.

Grade 1: Place Value, Time & Measurement · 14 topics

Tens and Ones [E] A two-digit number is some tens and some ones.
Building Two-Digit Numbers [E] Put tens and ones together to make a number.
10 More and 10 Less [E] Change the tens digit by one.
Counting by Tens [E] Skip-count 10, 20, 30, and so on.
Adding Tens [E] Add a multiple of ten to a two-digit number.
Comparing Two-Digit Numbers [M] Use <, >, or = to compare.
Telling Time to the Hour [E] Read a clock on the hour.
Telling Time to the Half-Hour [E] Read a clock on the half-hour.
Comparing Lengths [M] Order objects by length using clues.
Measuring Length in Units [E] Count how many whole units long an object is.
Putting Events in Order [E] Decide what comes first, next, and last.
Count to 120 [E] Count on past 100, all the way to 120.
Subtracting Tens [E] Take away 10, 20, 30 from a multiple of ten.
Measuring with Non-Standard Units [E] Lay same-size objects end to end and count them.

Grade 1: Geometry, Fractions & Data · 13 topics

Sides of 2D Shapes [E] Count the straight sides of a flat shape.
Vertices of 2D Shapes [E] Count the corners where sides meet.
Composing 2D Shapes [E] Put shapes together to build new shapes.
Naming 3D Shapes [E] Match solid shapes to real objects.
Halves and Fourths [E] Split a whole into equal fair shares.
Naming a Half and a Fourth [E] Say the name of one equal part.
Counting Data in Categories [E] Add up counts across up to three groups.
Reading a Picture Graph [E] Read one category from a chart.
More and Fewer from Data [E] Compare two groups to find how many more.
Fair Shares [E] Split a total into equal groups.
Reading Tally Marks [E] Count tally marks, five to a bundle.
Which Category Has the Most [E] Read three groups and find the biggest.
Interpreting Data: How Many More [E] Compare two of three categories to find the difference.

1st Grade Math - Depth · 40 topics

Add Within 20 [M] Add two numbers with a total of 20 or less.
Subtract Within 20 [M] Take away to find how many are left, within 20.
Doubles to 20 [M] Add a number to itself, up to 10 + 10.
Near Doubles [M] Add two numbers that are one apart using a double.
Adding by Making a Ten [M] Break a number apart to make a friendly ten first.
Missing Addends [M] Find the number that completes an addition.
Add Three Numbers [M] Add three numbers by looking for a friendly pair.
Fact Families [M] Use a known addition to find a subtraction.
Add Ten to a Number [M] Add one whole ten to a two-digit number.
Add Multiples of Ten [M] Add tens like you add ones.
Count to 120 [M] Keep counting past 100 all the way to 120.
Count by Tens to 120 [M] Skip-count by tens up toward 120.
How Many Tens [M] Read the tens digit of a two-digit number.
How Many Ones [M] Read the ones digit of a two-digit number.
Value of the Tens Digit [M] Tell the value the tens digit stands for.
Build a Number from Tens and Ones [M] Join tens and ones to make a two-digit number.
Ten More, Ten Less [M] Jump a whole ten up or down from a number.
Compare Two-Digit Numbers [M] Decide which two-digit number is greater.
Greater Than, Less Than, Equal [M] Choose the >, <, or = symbol that compares two numbers.
Order Three Numbers [M] Find the smallest of three two-digit numbers.
Tell Time to the Hour [M] Read a clock when the minute hand is on 12.
Tell Time to the Half-Hour [M] Understand what half past means on a clock.
Hours Later [M] Find the time a few whole hours later.
Count Nickels [M] Find the value of a handful of nickels.
Count Dimes [M] Find the value of a handful of dimes.
Count Mixed Coins [M] Add up the value of nickels and pennies together.
Measure Length with Units [M] Measure how long something is using same-size units.
Compare Two Lengths [M] Decide which of two objects is longer.
Order Objects by Length [M] Find the shortest of three objects.
Combine Lengths [M] Add two lengths placed end to end.
Defining Shape Attributes [M] Tell which features truly define a shape.
Compose Shapes [M] Combine smaller shapes to build a bigger one.
Halves [M] Understand cutting a whole into two equal parts.
Fourths (Quarters) [M] Understand cutting a whole into four equal parts.
Half of a Number [M] Split an even number into two equal parts.
Count Equal Shares [M] Match the name of a share to how many parts.
Skip Count by Twos [M] Count 2, 4, 6, 8 and keep the pattern going.
Skip Count by Fives [M] Count 5, 10, 15, 20 and keep the pattern going.
Compare Word Problems [M] Find how many more one person has than another.
Two-Step Word Problems [M] Solve a story with two changes in a row.

1st Grade Math - Deep II · 31 topics

Counting Back to Subtract [M] Subtract a small number by counting back from the bigger one.
Doubles Minus One [M] Add two numbers one apart using the higher double.
Making a Ten to Subtract [M] Subtract across ten by stopping at ten on the way.
Order Does Not Change the Sum [M] Use the fact that addends can be added in any order.
Ten-Plus Facts [M] Add a one-digit number to ten to make a teen.
Expanded Form [M] Break a two-digit number into its tens and ones values.
Two-Digit Number Words [M] Match a two-digit number word to its numeral.
One More, One Less to 120 [M] Add or take away one anywhere up to 120.
Numbers In Between [M] Name the two-digit number between two others.
Digital Clock Times [M] Match an o'clock or half-past time to a digital clock.
Count Quarters [M] Find the value of a few quarters.
Count Dimes and Pennies [M] Add the value of dimes and pennies together.
Count by Twenty-Fives [M] Skip-count 25, 50, 75, 100 like counting quarters.
How Many More Cents [M] Find how many more cents are needed to reach a price.
Build with Solid Shapes [M] Combine solid shapes to make a new solid.
Equal and Unequal Shares [M] Know that fair shares must be equal in size.
Thirds [M] Understand splitting a whole into three equal parts.
Bigger: a Half or a Fourth [M] Compare the size of a half to a fourth.
A Fourth of a Number [M] Split a number into four equal groups.
Name the Shaded Fraction [M] Say the fraction name for one shaded equal part.
Parts That Make a Whole [M] Count how many equal parts rebuild the whole.
How Many Fewer [M] Find how many fewer one group has than another.
Read a Bar Graph [M] Read the value of one bar on a bar graph.
Which Category Has the Fewest [M] Read three groups and find the smallest.
Add-To: Change Unknown [M] Find how many were added when the total is known.
Take-From: Start Unknown [M] Find the starting amount when some were taken away.
Put-Together: Missing Part [M] Find one part when the whole and the other part are known.
Greatest of Three Numbers [M] Find the biggest of three two-digit numbers.
How Much Longer [M] Find how much longer one object is than another.
Two-Digit Minus One-Digit [M] Subtract a one-digit number from the ones place.
True or False Subtraction [M] Decide which subtraction sentence is correct.

1st Grade - Addition & Subtraction Strategies (Deep) · 46 topics

Count On from the Bigger Number [H] Add by starting at the larger addend and counting on the smaller one.
Count On with Hops on a Number Line [H] Add on a number line by hopping forward one space for each one added.
Count Back with Hops on a Number Line [H] Subtract on a number line by hopping back one space for each one taken.
Count Up to Find a Difference [H] Find a difference by counting up from the smaller number to the larger.
Plus One, Plus Two, Plus Three [H] Add one, two or three to a number by naming the next counting numbers.
Partners That Make Ten [H] Name the number that pairs with a given number to make ten.
Break Apart to Make a Ten [H] Split the second addend so the first one grows into a ten.
Add Nine by Adding Ten [H] Add nine by adding ten and then taking one away.
Take Ten from a Teen [H] Subtract ten from a teen number to leave the ones.
Doubles Plus Two [H] Add two numbers that are two apart by using the smaller double.
Choose the Helping Double [H] Pick the doubles fact that helps with a near-doubles sum.
Doubles in an Array [H] Read a double from two equal rows of dots and total them.
Which Number Was Doubled [H] Find the number that was added to itself to give a total.
Use a Known Fact: One More [H] Find a new sum from a known sum when one addend grows by one.
Use a Known Fact: One Less [H] Find a new sum from a known sum when one addend shrinks by one.
The Matching Subtraction Fact [H] Write the true subtraction sentence that uses the numbers of a known sum.
Pairs with the Same Total [H] Recognize two addition pairs that have equal totals.
Give and Take to Add [H] Move ones from one addend to the other so the sum becomes ten plus ones.
Subtract by Thinking Addition [H] Solve a subtraction by finding the addend that completes the whole.
Check a Subtraction by Adding [H] Test a subtraction answer by adding it back to the number taken away.
Check an Addition by Subtracting [H] Test an addition answer by subtracting one addend from the total.
Take-From: How Many Were Taken [H] Find how many were taken away when the start and the rest are known.
Add Three: Make a Ten First [H] Add three numbers by pairing the two that make ten first.
Add Three: Use a Double First [H] Add three numbers by pairing the two equal ones first.
Three Numbers with One Missing [H] Find the third addend when three numbers and their total are given.
Choose the Easiest Pair First [H] Decide which two of three addends to add first to make the work easy.
Unknown in the First Place [H] Find the first addend when the second addend and the total are known.
Unknown at the Start of a Subtraction [H] Find the starting number when the amount taken and the rest are known.
Unknown Amount Taken Away [H] Find how much was subtracted when the start and the result are known.
Match the Story to the Equation [H] Choose the number sentence whose unknown sits where the story needs it.
Balance Both Sides [H] Make an equation true when both sides are additions.
Balance with a Subtraction [H] Make an equation true when one side is a subtraction.
True or False on Both Sides [H] Judge whether two additions on either side of the equal sign match.
The Total Written First [H] Solve an equation whose total is written before the equal sign.
True or False with Three Numbers [H] Judge whether a three-addend sentence gives the correct total.
Find the Number That Makes It True [H] Fill an unknown on the left so the two sides of an equation match.
Which Sign Makes It True [H] Choose the plus or minus sign that makes a number sentence true.
Compare: How Many More [H] Find the difference between two amounts shown side by side.
Compare: Find the Bigger Amount [H] Find the larger amount when one group has a stated number more.
Compare: Find the Smaller Amount [H] Find the smaller amount when the larger group has a stated number more.
Fewer Than: Find the Bigger Amount [H] Find the larger amount when the smaller group is a stated number fewer.
Two-Step: Put Together Twice [H] Combine two groups and then join a third to find a total.
Two-Step: Some Join, Some Leave [H] Work through a story where a group first grows and then shrinks.
Two-Step: Take Away Twice [H] Work through a story where two amounts are taken away one after another.
Two-Step: Compare Then Total [H] Find one amount from a comparison, then add both amounts together.
Two-Step: Find the Hidden Change [H] Find an unknown change that comes after a known first step.

1st Grade - Place Value, Measurement & Shapes (Deep) · 52 topics

Count Forward to 120 [H] Keep counting forward by ones from any number up to 120.
Missing Number on a Number Chart [H] Fill a blank square in a number chart using one more and ten more.
Count a Big Group by Tens [H] Count equal bags of ten and any loose ones to find a total.
Number Words Past One Hundred [H] Match a number word between 101 and 120 to its numeral.
Count Backward from 120 [H] Count backward by ones from numbers up to 120.
Read Base-Ten Blocks [H] Read a two-digit number from a picture of ten-rods and single cubes.
Extra Ones Make Another Ten [H] Rebuild a number when the ones are ten or more.
Trade a Ten for Ten Ones [H] Show the same number with fewer tens and more ones.
Ten Tens Make One Hundred [H] Count tens past one hundred, where ten tens make a hundred.
Jumps of Ten on a Number Line [H] Land on the right number after jumps of ten on a number line.
Ten More Past One Hundred [H] Find ten more or ten less for numbers near and past one hundred.
How Big Was the Jump [H] Decide whether a number changed by one or by ten, and by how many tens.
Ten More in a Story [H] Solve a story problem where an amount grows or shrinks by ten.
Compare Numbers Shown with Blocks [H] Compare two two-digit numbers shown as tens and ones.
Same Tens, Compare the Ones [H] Compare two-digit numbers that have the same tens digit.
Compare a Number to a Sum [H] Work out a sum of tens and ones, then compare it with another number.
Which Comparison Is True [H] Check comparison sentences and pick the true one.
Add Ones and Make a New Ten [H] Add a one-digit number when the ones make a new ten.
How Many More to the Next Ten [H] Find how many ones are needed to reach the next ten.
Missing One-Digit Addend [H] Find the missing one-digit addend in a two-digit addition.
Two-Digit Plus One-Digit Story [H] Solve a story problem that adds ones to a two-digit number.
The Tens Digit After Adding [H] Decide how many tens the answer has after adding ones.
How Many Tens in All [H] Add groups of tens and say the answer as a number of tens.
Add Tens to a Two-Digit Number [H] Add a multiple of ten to a two-digit number without changing the ones.
How Many Tens Were Added [H] Find the multiple of ten that was added to reach a total.
Adding Tens from a Graph [H] Read two multiples of ten from a bar graph and add them.
Subtract Tens from a Two-Digit Number [H] Take a multiple of ten away from a two-digit number.
How Many Tens Were Taken [H] Find the multiple of ten that was subtracted.
Taking Away Tens in a Story [H] Solve a story problem where whole tens are given away.
Fact Families with Tens [H] Match addition and subtraction facts made from the same three multiples of ten.
Compare Lengths Without Measuring [H] Compare two objects using a third object they were both compared to.
Rules for Fair Measuring [H] Apply the rules that make a length measurement fair.
Smaller Units, Bigger Number [H] Relate the size of the measuring unit to the size of the count.
Order Ribbons by Length in a Picture [H] Order three drawn objects by how many length units each one covers.
Measure from a Cube Picture [H] Count same-size units in a drawing to measure and compare lengths.
Where the Hour Hand Points [H] Read the hour hand at an o'clock time and at a half past time.
What the Minute Hand Tells [H] Use the minute hand to tell an o'clock time from a half past time.
Half an Hour Later [H] Find the time a half hour or an hour and a half after a given time.
Before or After a Given Time [H] Decide whether a clock time comes before or after another time.
How Many Half Hours [H] Count how many half hours fit inside a number of hours.
How Many in All Three Groups [H] Add every category in a graph to find the total.
Put Two Categories Together [H] Add two chosen categories from a three-category graph.
Find the Missing Bar [H] Use the total and the bars shown to find a missing category.
Most and Fewest: the Difference [H] Find the difference between the largest and smallest categories in a graph.
Sort a List into Categories [H] Organize a list of choices into categories and count them.
What Does Not Change a Shape [H] Separate the attributes that define a shape from those that do not.
Name the Shape from Its Clues [H] Name a flat shape from the number of sides and corners described.
Faces and Corners of Solid Shapes [H] Count the flat faces or corners of a common solid shape.
Which Solids Roll and Stack [H] Tell which solids roll and which stack, using their flat and curved parts.
How Many Triangles Fill the Shape [H] Count the smaller shapes needed to fill several copies of a bigger shape.
Cutting a Shape Makes New Shapes [H] Name the shapes made when a flat shape is cut with a straight line.
Equal Parts in More Than One Whole [H] Count halves or fourths across several wholes.

1st Grade - Addition, Subtraction & Place Value (Deep) · 42 topics

How Big Was the Hop [H] Counting from the start to the landing place gives the size of the hop.
Where the Hop Began [H] To find where a hop began, undo it: hop the same size the other way.
The Missing Number on the Line [H] Find the counting rule from the labels, then use it on the gap.
Equal Hops on the Line [H] Equal hops skip count, so the landing place and the hop count match up.
Empty Boxes in a Ten-Frame [H] Counters and empty boxes in a ten-frame always add up to ten.
Putting More Counters in the Frame [H] Count on from the counters shown; past ten the total becomes a teen.
Taking Counters Out of the Frame [H] Taking counters out leaves fewer counters and more empty boxes.
A Full Frame and Some More [H] A full frame is one ten, so a teen number is ten and the extra ones.
Ten and Some More [H] Filling the frame rewrites a hard sum as an easy ten-plus fact.
Landing on Ten First [H] Subtract from a teen in two easy hops: back to ten, then the rest.
Nothing Added, Everything Taken [H] Adding zero changes nothing, and taking a number from itself leaves zero.
Which Card Is Bigger [H] Work out each total first, then compare the totals.
Two More, Two Less [H] Change one addend by two and the total changes by two the same way.
One More Here, One Less There [H] Moving one from an addend to the other keeps the total the same.
The Same Fact, Ten Bigger [H] Adding ten to an addend adds ten to the total, and the ones stay put.
Which Fact Helps Most [H] Pick a helper fact that is close to the sum and easy to say.
Keeping Both Sides Equal [H] The equal sign says the two sides are worth the same amount.
Take-Away on Both Sides [H] Work out the side you can, then make the other side match it.
True or False with Tens [H] Adding tens to tens counts tens, so only the tens digit changes.
Another Name for a Number [H] One number has many names: sums and take-aways can all mean the same.
How Many More to Fill the Order [H] A missing addend is the gap between what you have and what you want.
How Many More to Twenty [H] Count on from where you are to twenty to find what is still missing.
Filling In a Part-Whole Table [H] The parts add up to the whole, so any one of them can be found.
Two Parts That Fit the Clue [H] Check every pair against both the total and the clue before choosing.
Three Groups in a Picture [H] Read each row of the picture, then join only the rows the question asks for.
Adding Four or Five Numbers [H] Add a long line of numbers two at a time, keeping a running total.
Which Numbers Make the Total [H] Test each list by adding it, and keep the one that lands on the total.
Fewer Than: Find the Smaller Amount [H] "Fewer than" names the smaller amount, so take the gap away.
Add-To: How Many Were There at First [H] When things were added, work backwards from the end to the start.
Making Two Amounts Match [H] The gap tells how many to add on; sharing the gap fairly halves it.
The Number You Do Not Need [H] Use only the numbers that answer the question asked.
Comparing Two Rows of a Table [H] Find the two rows the question names, then compare only those.
Is That Enough? [H] Compare what you have with what you need, then say the gap.
Finishing a Base-Ten Picture [H] Match the blocks to the digits: tens blocks to the tens, ones to the ones.
Swapping the Two Digits [H] Swapping the digits swaps their jobs, so the number changes a lot.
Number Riddles with Tens and Ones [H] Work out each digit from its clue, then write the tens digit first.
How Many Ten-Frames Does It Take [H] The tens digit counts full frames; the ones digit is what is left over.
Jumping Ten More Than Once [H] Each jump of ten changes only the tens digit, so count the jumps.
Ten More or Ten Less [H] Ten more moves the tens digit; one more moves the ones digit.
Adding Tens to a Block Picture [H] One more tens block is ten more, so only the tens digit moves.
Which Digit Changes [H] Adding a multiple of ten moves the tens digit and leaves the ones alone.
Tens First, Then Ones [H] Add the tens to the tens first, then deal with the ones.

1st Grade - Measurement, Time, Geometry & Data (Deep) · 42 topics

Which One Is the Longest [H] The longest object is the one with the most cubes in its row.
Which One Is the Shortest [H] The shortest object is the one with the fewest cubes in its row.
The One in the Middle [H] Ordering three lengths leaves one object between the other two.
Longer and Shorter from Clues [H] If A beats B and B beats C, then A beats C without any measuring.
Measuring with Cubes in a Row [H] Lay same-size cubes end to end and count them to measure a length.
The Gap Between Two Cube Rows [H] Line up two rows of cubes and count the extra cubes on the longer one.
Joining Lengths End to End [H] Two lengths joined end to end add; a missing piece is found by taking away.
Longer and Shorter Stories [H] Shorter means take the gap away; longer means add it on.
Does It Fit Inside [H] One thing fits inside another only when it is the shorter one.
O'Clock on a Clock Face [H] On the hour the long hand points at 12 and the short hand names the hour.
Half Past on a Clock Face [H] At half past the long hand points at 6 and the short hand has just passed the hour.
Whole Hours Later [H] One hour later moves the short hand on by one and leaves the long hand alone.
Half an Hour On from Now [H] Half an hour later turns o'clock into half past, and half past into the next o'clock.
Saying a Time Two Ways [H] The same time can be said in words or written with two dots.
Putting Times in Order [H] Earlier times have smaller hour numbers, and o'clock comes before half past.
Counting Whole Hours [H] Count the hours from one o'clock time up to another.
What Each Coin Is Worth [H] A penny is 1 cent, a nickel is 5 cents and a dime is 10 cents.
Adding Up a Purse of Coins [H] Count the dimes by tens, the nickels by fives, then add the pennies.
How Many Coins Make the Amount [H] Skip count by the coin's value until you reach the amount.
Who Has More Money [H] More coins is not always more money, so work out each total first.
Is That Enough Money [H] Add the coins up, then compare that total with the price.
Cents Left After Spending [H] Total the coins first, then take away what was spent.
Naming the Shape You See [H] A flat shape is named by how many straight sides it has.
Counting the Sides [H] A side is one straight edge, counted once all the way round the shape.
Counting the Corners [H] A corner is where two sides meet, and a flat shape has as many corners as sides.
Which Shape Has That Many Sides [H] Going from a side count back to a shape name is the same list read backwards.
What Really Makes the Shape [H] Sides and corners decide a shape's name; color, size and turning do not.
Making a New Shape from Shapes [H] Shapes pushed together with no gaps make one new, bigger shape.
Naming a Solid Shape [H] Solid shapes are named by their flat faces and their curved parts.
Solids All Around Us [H] Everyday objects match the solid shapes: balls, cans, hats and boxes.
The Flat Face of a Solid [H] The flat face of a solid is itself a flat shape you can name.
Sorting Shapes by Their Sides [H] Sorting a list of shapes means checking each name against the rule.
Naming One Equal Part [H] Two equal parts are halves and four equal parts are fourths.
How Many Pieces [H] The name of the part tells how many pieces the whole was cut into.
Fourths and Quarters [H] Fourth and quarter are two words for the same part of a whole.
Reading One Row of a Tally Chart [H] Tally marks come in gates of five, so count by fives and then by ones.
Which Group Has the Most [H] The biggest group is the row with the most tally marks.
Which Group Has the Fewest [H] The smallest group is the row with the fewest pictures.
How Many More Chose It [H] Match the two rows picture for picture; the extras are the difference.
How Many Altogether [H] Adding every row of a chart gives how many children were counted.
The Group That Is Not Shown [H] Take the shown groups away from the total to find the hidden group.
Sorting a Class List into Groups [H] Sorting a list means counting the rows that belong to each group.

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