
Buying Guide for Rulers

Why buy a ruler for school?
Rulers are extremely useful tools for measuring objects and drawing straight lines—sometimes both at once. As mentioned above, this means that in schools, they’re most commonly used in art and math classes. It’s extremely hard to draw a perfectly straight line freeform. Even if you have lines on the page, like with graph paper, it’s all too easy for your hand to slip. A hard, straight surface like a ruler makes a handy guide to lean against as you draw straight lines in pencil, pen, marker, or even chalk.
Rulers are equally important for measuring purposes as well. Most of us don’t know exactly how long an inch or centimeter is at a glance, even if we’re capable of making a fairly decent estimate. Rulers have built-in measurement unit markings along the edges, so you can take the guesswork out of measuring and ensure more exact and precise measurements.
What should you look for in a ruler?
- Units: Any good school ruler will have measurement markings along the side, and these should be clearly marked and easy to read. You’ll also want to consider which measurement units are marked on the ruler. Most rulers will be marked with both centimeters and inches, with the two different units on opposite edges. These types are incredibly useful since they account for both the imperial and metric systems.
- Length and Shape: Most school rulers will come in a long, thin, rectangular shape. They’re commonly known as desk rulers and are the type you’ll see in most classrooms or back-to-school kits. However, there are a few other shapes out there, namely half circle ones (protractors) and triangular ones. These will usually be more useful for older students as they learn subjects like geometry that involve measuring and calculating angles. In terms of length, most school rulers will be about a foot (12 inches) long, which will suit most K-12 students.
- Durability: A good ruler should not be easily broken or shattered, so look for ones made of real wood, rubber, or metal, preferably steel or stainless steel. Thick plastic rulers are also a good choice for younger kids since they’re waterproof, colorful, and inexpensive to replace, though they will snap and break much easier than wood, rubber, or metal. If you opt for a plastic ruler, make sure it’s made from either a sturdier type of plastic (like ABS) or more flexible plastic material that can hold up to a lot of bending and fidgeting.
What’s the difference between rulers and protractors?
Basically, all protractors are rulers, but not all rulers are protractors. More specifically, protractors are a type of specialty rulers that are shaped like half circles; they’re not solely straight-edged like standard desk rulers. In addition to measuring specific lengths and segments in straight lines like regular desk rulers, protractors are used to measure and draw angles. The straight edge of a protractor will serve as a more standard desk ruler, albeit an often shorter one than the average 12-inch model, while the circular side is meant for measuring and drawing acute, right, and obtuse angles.
Younger students probably won’t need a protractor ruler; they don’t usually appear on back-to-school lists until middle school. That said, protractors are also great for drawing curved lines and circles, so some younger kids might find them useful for that reason, even if they won’t be measuring angles just yet.
Our Picks for the Best Back-to-School Rulers
Mr. Pen Steel Rulers
Sturdy and durable, these traditional steel rulers offer measurements in both the metric and standard systems.
Pros: Sold in a pack of four, these ruler offers two sides to measure in both centimeters and inches. The large black numbers and notches on the silvery metal bodies make it easy to follow and measure. And since each ruler is made of stainless steel, they’re tougher and more durable than almost any other rulers on the market. The four rulers come in four different lengths (6, 8, 12, and 14 inches long), so you’ll receive smaller rulers that can easily fit into most pencil cases, a classic foot-long hand ruler, and one slightly longer than average for bigger objects. As a bonus, each ruler has a handy conversion table on the back that you can quickly refer to at any time.
Cons: Be careful when handling these rulers, as they have rather sharp edges. Also, when measuring, keep in mind that the measurements don’t start directly at the end of the ruler.
Bottom Line: You often can’t go wrong with the classics, and this set of traditional hand rulers is no exception. With four different sizes per pack, these are strong, durable hand rulers suitable for young students for home and school use alike.
Eagle Paper Puncher with Integrated Ruler
This ruler can be stored in a binder and has a built-in hole punch.
Pros: This isn’t just a ruler; it’s a ruler with a built-in hole punch. You’ll be able to punch holes in up to five sheets of paper at a time and accurately measure items up to 10 inches in length. The hole punch section is made from ABS plastic, and it has built-in binder holes, so you have the option to clip it right into a three-ring binder or portfolio. There’s also a built-in chip tray that catches any debris from the hole punching function. The tray is removable to make it easier to empty when full. And it’s available in three fun, bright colors.
Cons: This ruler is one-sided and only marked with inches, so it’s not good for measuring with the metric system. It also won’t fit in all binders; it’s only suitable for standard three-ring binders.
Bottom Line: This handy ruler offers a two-in-one function that most other models can’t match. Since it’s a ruler and a hole punch in one, you can cross two back-to-school items off your shopping list with this item.
Arteza Architect Scale Ruler
This three-sided aluminum ruler is ideal for architecture projects and blueprints.
Pros: This unusual, multi-sided ruler is quite distinct from a standard hand or school ruler. It’s triple-sided, with each side bearing two different scales for a total of six scales rather than the usual dual imperial/metric units that most rulers have. This makes it extra useful for drafting, blueprints, and other similar professional or educational projects. Each side is color-coded to make it easier to find the scale you’re looking for. The entire ruler is made from sturdy yet lightweight aluminum, so it’s plenty durable but isn’t a hassle to carry around, even with the extra sides.
Cons: Metal rulers often have sharper corners and edges than other types, and this model is no exception, especially considering its shape. Also note that the different units of measurement aren’t labeled, which may be confusing until you get the hang of using this ruler.
Bottom Line: This uniquely shaped ruler was specifically designed for architects, civil engineers, and other similar jobs, though there’s no reason students can’t use it too, especially if they’re studying in those fields. It’s great for precise measurements and easy drawing, whether you’re a career professional or a student.
Pros: The most common rulers used in schools are standard 12-inch rulers, and this model fits the bill. Marked with inches, half inches, quarter inches, and centimeters like any respectable school ruler, it’s made from wood rather than plastic, so it’s firmer and more durable than lighter plastic rulers that are common these days. The markings are accurate and evenly spaced, and the foot-long length is suitable for a surprisingly wide variety of measurement needs for how simple the ruler is. You’ll be able to measure lines and papers to furniture, electronics, and much more.
Cons: Though highly functional for what it is, this isn’t a ruler suitable for geometry or more advanced projects. If the ruler becomes warped, as sometimes happens with wooden models, it’ll be harder to use, and it doesn’t have any metric system markings on it besides centimeters.
Bottom Line: The classics are often classics for good reason, and that includes this traditional wooden ruler. Easy and straightforward to use and more durable than many modern rulers, it’s ideal for use in and out of school.
Mr. Pen Geometry Set
This geometry set comes with several rulers and protractors alongside a few other math-friendly tools.
Pros: You get a great bang for your buck with this ruler set, especially if you or your child will be studying geometry in school this year. It comes with not one, not two, but five different rulers, including two triangular ones and two protractors. One of the protractors also has a moveable arm that makes drawing and tracing different angles even easier. Each ruler is marked with both inches and centimeters. Five rulers make this an excellent value by themselves, but they’re not all you get in this kit. It also includes two metal compasses, pencil compasses, extra lead for the pencil compasses, a metal divider, a pencil sharpener, and more—15 different tools in total, plus a convenient storage pouch.
Cons: The tools are a bit on the smaller side, so some adults may not find them as useful as children or teenagers will. The rulers themselves are also a bit flimsier and not quite as sturdy as some other rulers on the market.
Bottom Line: This value pack of rulers and other tools is great for classrooms, offices, and art studios alike. The assortment of different rulers that come included and the other handy office and school supplies allow you to check multiple items off your shopping list in one go.
Final Thoughts
All different types of rulers, from desk rulers to protractors to yardsticks, are common classroom staples. Whether you need one for geometry homework, your latest art project, or cutting straight paper lines for arts and crafts, a ruler is the perfect tool.