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B. Number · Number Sense: Numbers to 50 and Fractions

Number Sense: Numbers to 50 and Fractions: Unit Review

B1.1 B1.2 B1.3 B1.4 B1.5 B1.6 B1.7 B1.8About 40 minutes
Learning goals
  • I can count, read, write, build and compare numbers to 50.
  • I can make a smart estimate and check it by counting.
  • I can share things fairly and name and compare halves, fourths and other equal shares.

Look how much you have learned!

In this unit you counted to 50 in lots of ways, read and wrote numbers, built them with tens and ones, compared and ordered them, and made smart estimates. Then you shared things fairly and learned about halves, fourths and other equal shares.

This review has a few questions from each lesson. Try each one, then press Show answer to check. If a question feels tricky, that's okay! Go back to that lesson for a little more practice.

Counting to 50 by 1s, 2s, 5s and 10s

1

Count by 5s from 25 to 50.

2

What number comes right after 19?

3

There are 3 hands. How many fingers? Count by 5s.

4

Count backward by 1s from 35 to 30.

Reading, Writing and Showing Numbers to 50

1

Write thirty-eight using digits.

2

Write 46 in words.

3

Draw tally marks for 9.

4

Lia came 1st in the race. Is the number telling how many, order or a label?

2 tens = 207 ones = 720 + 7= 27twenty-seven
27 is 2 tens and 7 ones. Each rod is a ten (count the 10 little squares in it), and each small cube is one. Count: 10, 20, 21, 22, 23, 24, 25, 26, 27.

Tens and Ones: Building and Breaking Apart Numbers

1

How many tens and ones are in 50?

2

What number is 1 ten and 18 ones?

3

What number goes with 3 to make 10?

4

Break apart 20 in two different ways.

Comparing and Ordering Numbers to 50

1

Which is greater: 26 or 62?

2

Order from least to greatest: 40, 4, 14, 24

3

What number is ten more than 18?

Estimating How Many

1

You see 4 full ten frames and 1 more dot. Which is the best estimate: 4, 14 or 40?

2

You estimated 30 leaves. You counted 33. Was your estimate close?

3

Why is 10 a good benchmark for estimating?

whole1 wholehalvesone halfone halffourthsone fourthone fourthone fourthone fourth
The same bar cut into halves and into fourths. One fourth is smaller than one half, and the dashed line shows that two fourths are the same length as one half.

Fair Sharing with 2 and 4 Friends

1

Share 8 tarts fairly among 4 friends. How many does each get?

2

Share 15 crackers between 2 friends. How many does each get? How many are left over?

3

Ali cut a muffin into 2 pieces: one big and one small. Is that a fair share?

Halves and Fourths

1

A pizza is cut into 4 equal parts. You eat 1 part. How many fourths are left?

2

Is two fourths of a pizza the same amount as one half of the same pizza?

3

How many halves make one whole?

More Sharers, Smaller Shares: Comparing Fractions

1

Which is bigger: one eighth or one fourth of the same cake?

2

6 people share a pie fairly. What part does each person get?

3

Order from greatest to least: one tenth, one half, one fifth.

Just for fun

Why was the math book sad?

It had too many problems!

How to use this review

For parents: let your child try each section on their own first, using objects (buttons, cereal, paper strips) or drawings whenever they want. Check answers together with the Show answer button.

  • Do one or two sections a day rather than the whole review at once.
  • Each section is named after a lesson. If your child misses more than one question in a section, go back to that lesson and redo its More practice questions.
  • Ask "How do you know?" even when the answer is right. Explaining is a big part of Grade 1 math.
  • Finish with the quiz to see how everything fits together.
Check your understanding

Quiz

1.

Count by 2s: 16, 18, 20, ___. What comes next?

2.

How many fingers are on 7 hands?

3.

Which number is forty-nine?

4.

What number is 2 tens and 14 ones?

5.

Which number is the greatest?

6.

What number is one more than 49?

7.

A jar has about 3 groups of 10 marbles. What is the best estimate?

8.

Share 12 apples fairly between 2 friends. How many does each get?

9.

Which is the same amount as one half of a pizza?

10.

Which share of the same cake is the smallest?

For parents and teachers

Using the review to decide what to revisit: each practice section is named after one lesson, so mistakes point to where to go back.

  • Skipping numbers, mixing up 2s, 5s and 10s, or getting stuck after 29, 39 or 49: revisit Counting to 50 by 1s, 2s, 5s and 10s.
  • Writing 35 as 305 or 53, or mixing up number words like forty and fourteen: revisit Reading, Writing and Showing Numbers to 50.
  • Trouble with tens and ones, especially "1 ten and 18 ones" type questions: revisit Tens and Ones and use real bundles of 10.
  • Saying 29 is greater than 31 because 9 is bigger than 1: revisit Comparing and Ordering Numbers to 50 (compare the tens first).
  • Wild guesses (like 5 or 500 for a jar of 30) or counting instead of estimating: revisit Estimating How Many with a visible group of 10.
  • Uneven sharing or not knowing what to do with leftovers: revisit Fair Sharing with 2 and 4 Friends and act it out by dealing real snacks.
  • Calling unequal pieces halves, or not seeing that two fourths equals one half: revisit Halves and Fourths with paper folding.
  • Thinking one tenth is bigger than one half because 10 is bigger than 2: revisit More Sharers, Smaller Shares with paper strips of the same length.

If your child gets a whole section right, celebrate and move on. A mistake or two is normal; look for patterns rather than single slips.