How to place decimals on the number line practice

A number line works like a zoom lens. Between 0.03 and 0.04 there is room for 0.031, 0.032 and every thousandth up to 0.039, and the page draws that room out wide so your child can see it.

The four lines also change the size of each jump. From 2.0 to 3.0 the step is one tenth. From 5.0 to 5.2 it is two hundredths, and from 7.0 to 7.7 it is seven hundredths, so your child must first find the step: the gap divided by ten. That planning is the heart of finding the step size on a number line.

The standard is 6.NS.C.6, understanding a rational number as a point on the number line.

Cover page 2 and start with the last line, 7.0 to 7.7. Ask, "How many jumps are there, and how big is each one?" Many kids write 7.1, 7.2, 7.3 because the first line went up in tenths. Count the gaps together: ten jumps share 0.7, so each is 0.07, and the boxes read 7.07, 7.14, 7.21 and on up to 7.63.

On the 5.0 to 5.2 line, the middle box is 5.10. Ask, "Is 5.10 the same as 5.1?" It is, and that is a good moment to say why.

The big and small dots on the stems only alternate the box heights; they do not mean different sizes.

A measuring cup is a number line standing up: the marks between 0 and 1 cup split it into equal parts. Ask your child where 0.5 or 0.75 of a cup would sit. A car trip works too: when the next exit is 2.4 miles away, the trip meter counts tenths until you get there.

Full House: An Invitation to Fractions by Dayle Ann Dodds shares one cake into equal slices for everyone at an inn. Draw that cake as a line from 0 to 1 and the cuts become points.

Celebrate the effort: "You found the step before you wrote a single number." This sheet closes the decimals series; going back to the grid sheet shows the same tenths as columns.