15Q20M

How far behind in math is my child? A 20-minute home check

By 15Q20M Editorial · Last updated

You can find out in twenty minutes at the kitchen table. If your child is in fifth or sixth grade, give them the six fourth grade problems below with no help and no calculator, and note which ones stall. One or two misses name the skills to rebuild. Three or more misses point past any single skill to the foundation.

What does "behind in math" actually mean?

Math stacks. Every year's work sits on a few skills from the year before, so one skill that never became automatic keeps surfacing in this year's assignments. A child can know the multiplication facts cold, handle word problems, and still stall every time a fraction turns up with an unfamiliar denominator.

It spreads because number work carries most of the load. In our own Grade 4 workbook, base ten and fractions together take close to six problems in every ten, which is why a weak skill inside either one surfaces almost daily.

Across 1,200 Common Core tagged problems in our Grade 4 practice bank, number and operations in base ten accounts for 33.7% of the year and fractions for 25.8%, just under six problems in every ten. Measurement and data take 20.8%, operations and algebraic thinking 12.1%, geometry 7.7%.
Source: 15Q20M Grade 4 question bank, our own workbook data (computed 2026-09-12)

What does a grade-equivalent score actually tell me?

If the school sent home a score that reads like a grade level, read the fine print before you act on it. A grade-equivalent score of 6.2 on a fourth grade test does not mean your child did sixth grade math. It means the test's norms project that a typical sixth grader in the second month of the year would score about the same. Each grade is normed on a different group taking a different test, so the two children were never compared on the same questions. The number carries no information about which skills they have and none about which ones they are missing.

"Because grade-equivalent scores are misleading and so often misinterpreted, especially by parents, most educators and psychologists believe they should not be used at all."
Source: Woolfolk, Educational Psychology (1990), quoted in a SUNY Cortland measurement reference

Problems are more useful than scores here. A problem your child cannot finish tells you its own name: equivalent fractions, long division, converting meters to centimeters.

How can I tell how far behind my child is without a test?

The six problems below are fourth grade work, taken from our Grade 4 workbook. Use them if your child is in fifth or sixth grade, because they cover the fourth grade skills that fifth grade work sits directly on top of: two-digit multiplication, division with a one-digit divisor, equivalent fractions, subtracting fractions with like denominators, rounding for an estimate, and measurement conversion inside a word problem. For a fourth grader these are this year's problems, not last year's, so a miss may only mean the skill is still being taught. Use the pattern guide linked at the end.

Twenty minutes, paper, a pencil, no calculator, and no help from you. Do not read the problem aloud, and do not step in when the pencil stops moving. Give the whole set even if the first one goes badly, because one panicked start tells you very little.

#ProblemSkill it checksAnswer
1A gym installs 24 rows of lockers with 16 lockers in each row. After inspection, 38 lockers are removed for repair. How many lockers remain?Two-digit multiplication, then subtraction (4.NBT.B.5, 4.NBT.B.4)346
2A farmer collects 720 eggs and packs them equally into 9 cartons. She then adds 15 more eggs from a small henhouse into one carton. How many eggs are in that carton now?Division by a one-digit number, then addition (4.NBT.B.6)95
3A student writes 3/4 = 5/8. What is the correct numerator over 8?Equivalent fractions (4.NF.A.1)6
4A pan has 9/8 pound of butter. A baker uses 4/8 pound for cookies, then uses 2/8 pound for bread. How much butter is left in the pan?Subtracting fractions with like denominators, two steps (4.NF.B.3)3/8
5Estimate 38 × 21 by rounding both to the nearest ten.Rounding, then multiplying (4.NBT.A.3, 4.NBT.B.5)800
6A shelf is 3 m long. One book is 80 cm wide and another is 65 cm wide. How many centimeters of shelf space are left after placing both books?Converting meters to centimeters, then two subtractions (4.MD.A.2)155

Write down two things for each problem: right or wrong, and how long it took by the clock. A correct answer that took four minutes of finger counting is a different result from a correct answer that took twenty seconds.

How do I know if it is one gap or a bigger problem?

What you sawWhat it points toWhat to do next
All six right, and none of them draggedThese six fourth grade skills are holding. Six problems cannot clear a whole year.Stay on this year's content, and re-check with this year's work if the trouble continues.
All six right, but two or more took far longer than the restThe skill is there but slow.Ten minutes a day on facts, then re-time the same skills with fresh numbers.
1 or 2 wrongThat many named skills to rebuild.Work each one daily until it runs without effort, then re-check with new numbers.
3 or more wrongWider than one skill, whether the misses cluster in one topic or spread across several.Work a structured plan one skill at a time, and take the sheet to the teacher.

One wrong answer only tells you where to look next. Six problems cannot separate a real gap from a misread question or a bad night. Before you build a plan around any single miss, write two more problems that test the same skill with different numbers and give those instead.

The speed row is the one families skip, because homework does not have a clock on it. A child who can do the math slowly looks fine at the kitchen table and falls apart on a timed test, since arithmetic that should run in the background is eating the whole period. The federal intervention guide gives fact retrieval its own ten minutes in every session.

"Interventions at all grade levels should devote about 10 minutes in each session to building fluent retrieval of basic arithmetic facts" (moderate evidence). The same guide opens with: "Screen all students to identify those at risk for potential mathematics difficulties and provide interventions to students identified as at risk" (moderate evidence).
Source: IES What Works Clearinghouse, RtI Mathematics practice guide

If the gap is fractions: the 3 places they get hard

How long does it take to catch up in math?

How long one skill takes depends on the skill and the child, and anyone who quotes you a number in advance is guessing. What you can settle in advance is the schedule for checking. Schools have a rule for that, and it is stricter than most kitchen tables.

"If at least three weeks of instruction have passed and six data points have been collected, examine the four most recent data points." For a trend line, "at least four weeks of instruction" and eight data points are required. The four points are compared against a goal line set in advance: all four above it means raise the goal, all four below it means consider adapting the intervention, and a mix means keep collecting data.
Source: National Center on Intensive Intervention, Decision Rules for Analyzing Academic Progress Monitoring Data (AIR, 2024)

That rule was written for standardized probes given by someone trained to give them, so at home you are borrowing its schedule and not running its procedure. Two parts of it still travel. The first is that you need a target written down before the first session, because a score means nothing without one. Use a fixed set of ten problems on that one skill, and record two numbers at each check: how many of the ten came out right, and how long the ten took. Write both at the top of the log on day one. The second is patience with your own data. The rule asks for three weeks and six scores, both, so at two checks a week no single bad Tuesday arrives anywhere near a decision.

One more thing sits outside that rule, and it is the one people get wrong. Never re-use the same six problems. Your child will remember 346 and 95 long before the skill becomes automatic, and the score will rise while nothing underneath it changes. Keep the structure of each problem and change the numbers every time, holding the difficulty still: same digit counts, same regrouping or none, same denominators. Swap 24 × 16 for 78 × 99 and you have built a harder test, and the score will fall for the wrong reason.

On why repeated measurement needs parallel forms: "if we give an easy form, we would imagine a high rate of growth. If we give hard forms we would imagine maybe even a negative form of growth." Forms should be "designed to be as close as possible, as equivalent as possible" so that growth reflects "true growth and not just an accident of the form."
Source: National Center on Intensive Intervention, Lee Branum-Martin on parallel forms

So the working answer is three to four weeks per skill before the data says anything, worked one skill at a time. A summer will not rebuild a year of instruction, whatever the back of the box says, though three or four rounds of that cycle fit inside one.

Found a gap? The 4-week catch-up plan, step by step

How much daily math practice does a 5th grader actually need?

When should I ask the school instead?

Bring the log. Four weeks of dated scores starts a different conversation than "he seems behind in math." Ask what the school's own screening shows, what is already happening in class, and what would trigger extra support. Screening every student is the first recommendation in the federal guide, so ask what is already on file before you ask for new testing.

Go sooner than four weeks if the misses covered every topic, if your child cannot read the problem well enough to begin, or if math has started producing tears. Those belong with the teacher on Monday.

Try a free sample day: one full 20-minute session, scored in the app

Write the six problems out tonight. Change the numbers before you use them again.

If your child is in 4th grade: the four patterns and what to practice

If your child is in 6th grade: why the year gets hard

Frequently asked questions

How far behind is "a year behind" in math?

The phrase usually comes from a score rather than from a list of skills, which is why it is hard to act on. A grade-equivalent number compares your child against a norm group and says nothing about which skills are missing. Six problems from the previous grade will name them in twenty minutes, and the count of misses tells you whether you are looking at one skill or several.

Can my child catch up a full grade level over the summer?

No. A summer will not replace a year of instruction, and a program that promises it is selling something. What fits in a summer is three or four rounds of the same cycle: pick one skill, practice it daily, score it every session with fresh numbers, and decide after three to four weeks whether it is working.

Should I ask the school to test my child?

Ask what their screening already shows before you ask for new testing. Screening every student is the first recommendation in the federal intervention guide, so it is worth asking what the school already has before paying for anything new. Bring four weeks of dated scores so the conversation starts with evidence instead of a worry.

Sources

Research citations link to the original papers. Statistics are checked against their primary source.

See the routine in action.

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