Dividing numbers up to 4 digits by a 1digit number
In a nutshell
Division is the inverse of multiplication. Four digit numbers are whole numbers between $1000$ and $9999$. They can primarily be divided by a onedigit number using two methods: chunking and short division.
Chunking
The chunking method separates four digit numbers into multiple easy to divide chunks in order to divide a four digit number by a one digit number.
Example 1
Calculate: $2500 \div 5.$
$2500$ can be split into two smaller "chunks" of $2000$ and $500$.
$\begin{aligned} 2000\div5 &= 400 \\ 500\div5&=100 \\ \\ 400+100&=500 \\ \end{aligned}$
$2500\div5 = \underline{500}$
Note: Use chunking for simple four digit numbers such as: $1000, 4500, 8000$.
Short division
Short division is also known as the "bus stop" method. To perform short division:
PROCEDURE
$1$
 Write the number your are dividing by under the "bus stop" and the number being divided as follows: $5000\div5 \rightarrow 5\overline{\smash{)}5000}$.

$2$
 Starting from the lefthand side of the number being divided, find how many times the divisor goes into the first digit. 
$3$  Write the answer above the "bus stop" and carry over any remainders to the next digit. 
$4$
 Repeat the procedure for the next digit. 
Example 2
Calculate: $5740 \div 4 .$
Write $4$ outside the bus stop and $5740$ inside the bus stop. Begin by finding how many $4$s go into $5$.
$4\overline{\smash{)}5740}$
$5 \div 4= 1\space remainder \ 1$
Write the answer $1$ above $5$. Write the remainder $1$ in front of $7$. Work out how many $4$s go into $17$.
$4\overset{1\,\,\,\,\,\,\,\,\,\,\,\,}{\overline{\smash{)}5~^1\!740}}$
$17\div 4 = 4\space remainder\space 1$
Write the answer $4$ above $7$. Write the remainder $1$ in front of $4$. Work out how many $4$s go into $14$.
$4\overset{\,\,1\,\,4\,\,\,\,\,\,\,\,\,\,}{\overline{\smash{)}57~^1\!40}}$
$14 \div 4 = 3 \space remainder \space 2$
Write the answer $3$ above $4$. Write the remainder $2$ before $0$. Lastly, work out how many $4$s go in $20$.
$4\overset{\,\,\,1\,\,4\,\,3\,\,\,\,\,\,\,\,}{\overline{\smash{)}574~^2\!0}}$
$20\div 4 = 5$
$4\overset{\,\,\,1\,\,4\,\,3\,\,5\,}{\overline{\smash{)}574~\!0}}$
$5740 \div 5 = \underline{1435}$
Remainders
Onedigit numbers do not always fit into a four digit number. The amount which is left over after division is known as a remainder.
Example 3
Use the chunking method to solve: $1004\div5.$
$1004$ can be split into three smaller "chunks" of $500$ and $500$ and $4$.
$\begin{aligned} 500\div5 &= 100 \\ 500\div5&=100 \\ \\ 100+100&=200 \\ \end{aligned}$
$4$ is not divisible by $5$.
$1004\div5 = \underline{200\space remainder\space 4}$
Example 4
Use short division to solve: $3964\div3$.
Write $3$ outside the bus stop and $3964$ inside the bus stop.
$3{\overline{\smash{)}3964}}$
Find how many $3$'s first fit into $3$, $9$ and $6$. Write the answers, $1$, $3$ and $2$ above each number respectively.
$3\overset{\,\,\,\,1\,3\,\,2\,\,\,\,}{\overline{\smash{)}3964}}$
$4$ is not wholly divisible by $3$.
Find the largest whole division you can perform.
$3\div3=1$
Write $1$ above $4$.
$3\overset{\,\,\,\,1\,3\,\,2\,\,1\,\,}{\overline{\smash{)}3964}}$
Find the remainder.
$\begin{aligned} 3\times1 = 3 \\ 43=1 \end{aligned}$
$3964\div3 = \underline{1321\space remainder\space 4}$