Free · Ready to print · Letter & A4
Types of angles
Need a types of angles within reach? Print it for the wall, then hand off to the practice sheets below.
- Letter & A4 ready
- Nothing to fill in
- Reprint it any time
Reference chart
Types of angles
Acute angle
Less than 90°
Right angle
Exactly 90°
Obtuse angle
Between 90° and 180°
Straight angle
Exactly 180°
Reflex angle
More than 180°
Adjacent angles
A shared side
Complementary
The two add to 90°
Supplementary
The two add to 180°
Vertical angles
Opposite, and equal
Long arms do not make a bigger angle. The arrows say the arms carry on for ever — what you are measuring is the turn between them, and nothing else on the drawing.
What's on this chart
The five sizes are one fact each and a child can hold them in a morning: less than 90°, exactly 90°, between 90° and 180°, exactly 180°, more than 180°. What makes them worth a wall chart is that the words arrive before the protractor does. A question that says "is this angle acute or obtuse" is asking for a judgement by eye against a right angle, and a page where all five sit side by side is what that judgement gets built from.
Why this chart helps
Every arm on this page ends in an arrowhead, and that is the one drawing decision here worth defending. The commonest mistake with angles at this age is not arithmetic — it is believing that the angle with the longer lines is the bigger one. An arm that stops is a line segment and invites the comparison; an arrow says the arm runs on for ever, so there is nothing to compare but the turn itself. Two angles of 40° drawn at different scales are the same angle, and the arrows are what make that visible without saying it.
More printable charts
Multiplication table Child does: Read a row across and a column down to the square where they meet. Print this chart 
Addition table Child does: Follow a row and a column to the square where the two numbers meet. Print this chart 
Subtraction table Child does: Start on the number being taken from, then read across to what is taken away. Print this chart 
Division table Child does: Find the family being divided by, then read down it to the answer. Print this chart 
Hundreds chart Child does: Count, skip count, or add ten by moving one square straight down. Print this chart 
Number bonds to 10 Child does: Read each row of counters and say the two numbers that make ten. Print this chart 
Fraction wall Child does: Line two rows up to see which fractions are the same width. Print this chart 
Place value chart Child does: Put each digit in its column and read what that digit is worth. Print this chart 
Number line 0–20 Child does: Count on or back by hopping along the line one number at a time. Print this chart 
Prime numbers to 50 Child does: Check whether a number is marked before trying to break it into factors. Print this chart 
Prime numbers to 100 Child does: Find the primes on the grid and see the pattern the multiples leave behind. Print this chart 
Prime numbers to 150 Child does: Look a number up on the grid instead of testing it for factors. Print this chart 
Prime numbers to 200 Child does: Tell a prime from a composite at a glance while factoring or simplifying. Print this chart 
Factors chart Child does: Read off every factor of a number before simplifying or finding a common one. Print this chart 
Divisibility rules Child does: Run one quick test in their head instead of starting a division. Print this chart 
Fraction, decimal & percent Child does: Swap the same amount between a fraction, a decimal, and a percent. Print this chart 
Fraction rules Child does: Check a fraction answer against the rule before doing the arithmetic. Print this chart 
Roman numerals Child does: Build or read a numeral using the seven symbols and the three rules. Print this chart 
Measurement conversions Child does: Look the conversion up, then decide whether to multiply or divide. Print this chart 
Multiplication table 1–20 Child does: Look up a fact past the twelves without working it out. Print this chart 
Squares and cubes Child does: Read off a square or a cube instead of multiplying it out. Print this chart 
Multiples chart Child does: Run a finger along two rows until the same number appears in both. Print this chart 
Number bonds to 20 Child does: Count the two colors in a row and say the pair that makes twenty. Print this chart 
Decimal place value Child does: Place a digit in its column and read what the digit is worth. Print this chart 
Telling the time Child does: Read the hour inside the dial and the minutes printed outside it. Print this chart 
Order of operations Child does: Work down the ranks, taking each one left to right before the next. Print this chart 
Positive and negative numbers Child does: Check which operation you are doing before deciding the answer's sign. Print this chart 
Rounding rules Child does: Find the place, look at the digit beside it, then decide. Print this chart 
Mental math tricks Child does: Swap the hard number for an easy one before you start calculating. Print this chart 
Perimeter formulas Child does: Follow the traced edge on the figure, then read the formula under it. Print this chart 
Area formulas Child does: Match your shape to a figure and use the letters drawn on it. Print this chart 
Volume formulas Child does: Find your solid, then multiply the base area by how tall it stands. Print this chart 
Surface area formulas Child does: Unfold the solid in your head and add up every flat face. Print this chart