What should my child know about place value by the end of first grade?

Typically: that a two-digit number is made of tens and ones, that 10, 20, 30 and so on are that many tens, and that they can compare two two-digit numbers using >, <, or =. Hundreds are usually introduced in second grade.

My child keeps writing 71 instead of 17. Is that a problem?

It is very common and specific to teen numbers, because we say the ones part first. It usually clears up with practice saying '17 is one ten and seven ones' before writing it. It is worth working on, since reversed teens cause errors in addition later.

Do we need base-ten blocks at home?

Not required. Groups of ten of anything — pasta, buttons, pennies, or fingers of family members — work for the bundling idea. Evelyn can direct a child to count and group whatever is on hand.

How is this different from counting practice?

Counting is about saying numbers in order and matching them to objects. Place value is about what the written digits mean — that the 5 in 52 is worth fifty. A child can count to 100 accurately and still not know how many tens are in 52.

Place Value

Q: My child keeps writing 71 instead of 17. Is that a problem?

It is very common and specific to teen numbers, because we say the ones part first. It usually clears up with practice saying '17 is one ten and seven ones' before writing it. It is worth working on, since reversed teens cause errors in addition later.

Q: Do we need base-ten blocks at home?

Not required. Groups of ten of anything — pasta, buttons, pennies, or fingers of family members — work for the bundling idea. Evelyn can direct a child to count and group whatever is on hand.

Q: How is this different from counting practice?

Counting is about saying numbers in order and matching them to objects. Place value is about what the written digits mean — that the 5 in 52 is worth fifty. A child can count to 100 accurately and still not know how many tens are in 52.

Elementary (K-2) · Mathematics

Place value is the idea that where a digit sits in a number tells you how much it is worth — the 3 in 34 means three tens, not three. In K-2 this grows from seeing 10 as one bundle of ten ones, to reading and writing two-digit numbers as tens and ones, to comparing numbers and working with hundreds by the end of second grade. Evelyn Tutor works through this by voice, asking a child to say what each digit is worth, count on by tens, and explain their reasoning out loud.

Start a session on Place Value

What this covers

Seeing 10 ones as one group of ten, and naming teen numbers as 'ten and some more' (14 = 1 ten and 4 ones)
Reading, saying, and writing two-digit numbers, and telling how many tens and how many ones are in each
Building the same number more than one way (35 as 3 tens 5 ones, or 2 tens 15 ones) and unbundling a ten into ten ones
Comparing two-digit numbers using tens first, then ones, with the symbols >, <, and =
Counting by tens from any number (37, 47, 57...) and adding or subtracting 10 mentally
Grade 2 extension: hundreds, reading three-digit numbers, and expanded form such as 342 = 300 + 40 + 2

Where learners get stuck

Writing 61 for 'sixteen' or 41 for 'fourteen': English says the ones part first in teen numbers — 'six-teen' — so a child writing what they hear puts the 6 down first. The number word order and the written order disagree only for the teens, which is why 21 through 99 usually cause no trouble.
Saying 19 is bigger than 21 because 9 is bigger than 1: The child is comparing digits as separate single numbers instead of comparing the tens first. This is normal until the tens place is genuinely understood as a quantity of ten-groups rather than just a digit sitting on the left.
Reading 43 as 'four and three' or 'forty and three' without knowing what the 4 stands for: Number names can be memorised as labels before the quantity behind them is built. A child may read every two-digit number correctly and still not know that 43 contains 4 tens, which shows up later as difficulty with regrouping in addition.

What a session looks like

Sessions run about 15-25 minutes and are spoken, not typed. Evelyn asks the child to say numbers aloud, count groups of ten, and answer questions like 'how many tens are in 58?' or 'which is more, 62 or 71, and how do you know?'. Because a young child may not be reading fluently, work is described in words rather than shown on screen, and physical counters, coins, or ten-frames at home can be used alongside. Evelyn slows down, re-asks, and gives smaller numbers when an answer shows the tens idea has not landed yet.

Helpful to know first

Counts aloud to at least 20, and ideally toward 100, without skipping numbers
Recognises and can say written numerals 0-9
Can count a set of objects one at a time and say how many there are in total
For the hundreds work: confident with tens and ones in two-digit numbers first

Questions

What should my child know about place value by the end of first grade?: Typically: that a two-digit number is made of tens and ones, that 10, 20, 30 and so on are that many tens, and that they can compare two two-digit numbers using >, <, or =. Hundreds are usually introduced in second grade.
My child keeps writing 71 instead of 17. Is that a problem?: It is very common and specific to teen numbers, because we say the ones part first. It usually clears up with practice saying '17 is one ten and seven ones' before writing it. It is worth working on, since reversed teens cause errors in addition later.
Do we need base-ten blocks at home?: Not required. Groups of ten of anything — pasta, buttons, pennies, or fingers of family members — work for the bundling idea. Evelyn can direct a child to count and group whatever is on hand.
How is this different from counting practice?: Counting is about saying numbers in order and matching them to objects. Place value is about what the written digits mean — that the 5 in 52 is worth fifty. A child can count to 100 accurately and still not know how many tens are in 52.