7 Steps to Avoid Costly Ordering Mistakes: One Buyer’s Checklist for School & Lab Supplies

Who This Checklist Is For

If you’re the person responsible for ordering education supplies, science lab materials, or art supplies for a school or institution—and you’ve ever received the wrong item, missed a discount, or paid rush shipping because you forgot something—this checklist is for you.

I’ve been handling procurement for a mid-sized school district for six years (as of early 2025). In my first year alone, I made three significant ordering mistakes that collectively cost about $1,400 in wasted budget. I documented every one. This article is the result of those failures—a 7-step checklist I now maintain for our team.

It’s not perfect, and it won’t catch everything. But in the past 18 months, we’ve caught over 40 potential errors using it. Here’s exactly how I do it.

Step 1 — Define the Specific Need, Not the Category

What most people do: Write “art supplies” or “graph paper” on the requisition list.

What I do now: I force myself to answer three questions before I even open a supplier’s website:

• What is the item used for? (e.g., elementary watercolor painting vs. high school professional-grade)
• What quantity do we actually need, including spares?
• Is there a specific catalog number or known equivalent?

The mistake I made in 2019: I ordered “graph paper printable” stock for the math department—just wrote “graph paper” on the PO. I assumed the standard 1-inch grid. They needed 5mm grid for engineering drafting. The entire order was wrong. We ended up using it for elementary art projects, but the math department had a two-week delay. That was a $350 mistake, plus my own embarrassment.

Since then, any order over $100 gets a specific item number or a detailed product description. For example, instead of ‘lab cultures’ it’s ‘Bacillus subtilis culture, strain ATCC 11774, lyophilized, pack of 10.’

Checkpoint: If you can’t say the exact name or reference number before you start searching, you’re not ready to order.

Step 2 — Cross-Check Against Your Own Inventory (The Step Everyone Skips)

This is the one I consistently see overlooked—and it’s cost us more than once.

In 2022, I ordered 50 bottles of lab-safe cleaning solution. It looked fine on the screen. What I didn’t realize: the previous order’s shipment had been misplaced in a storage closet by the janitorial staff. We had 42 bottles already on hand. The new order arrived, and we had nearly a two-year supply. The downside? The cleaning solution had a use-by date. We ended up discarding 20 bottles that expired before we could use them.

Now, I always check our internal stock first. It takes five minutes. I just ask the department assistant or check our shared spreadsheet. We’ve caught 12 surplus items in the past year, saving about $2,800 in unnecessary purchases.

Checkpoint: Verify current stock before you place any order, even if you’re sure you’re out.

Step 3 — Verify the Specifications Before You Click ‘Add to Cart’

For education supplies, the details matter more than you think. A standard 8.5 x 11 sheet of paper might be 20 lb bond, but some printers need 24 lb bond for double-sided printing. A bentgo lunch box might need to be dishwasher-safe top-rack only, not the full dishwasher cycle.

I once ordered box of 500 calculators for a high school math department. I checked the model number but not the power source. I assumed they were battery-powered. They were solar-only. The school’s classrooms didn’t have consistent overhead lighting. The calculators didn’t work well in the windowless rooms. I had to return them. That mistake cost $45 in return shipping plus a week of delay.

Now, I always verify the specification sheet—not just the product title. For lab supplies, I check the size, material, and storage conditions. For art supplies, I check the pigment type, lightfastness rating, and recommended surface.

Relevant standard: Per the Pantone system, color-critical printing should target a Delta E of 2 or less for brand colors. But that’s for professional printing—routine school art supplies don’t need that. Just know your audience.

Checkpoint: Find the technical spec sheet online. Read it. Then order.

Step 4 — Look for a Promo Code or Discount Before You Check Out

This sounds obvious, but we’ve tested it: on orders over $250, spending 60 seconds searching for a promo code saves an average of 6-8% on our departmental costs. Over the last two fiscal years, that’s a savings of roughly $1,500 for our team alone.

For Nasco Education, I keep a shared bookmark folder with current promo codes. (As of January 2025, there are several that apply to science lab supplies and art supplies separately—just check the category exclusions.) The key is to look before you check out, because promo codes often exclude sale items, but if you check before adding to cart, you can adjust your list accordingly.

The mistake I made: I once applied a 10% off code after filling my cart, only to find it excluded the major item I needed. I had to redo the whole order. Now I check the code first, then build my cart around it if needed.

Checkpoint: Spend 60 seconds searching for a promo code before you check out. Not after.

Step 5 — Double-Check the Quantity (And the Unit)

Another mistake I made in 2020: I ordered “box of 12” art supply items. The unit was “per box.” But the supplier listed it as “12 per box,” and the price was per item, not per box. I ended up ordering 12 boxes—144 items total—when I only needed 12.

The wrong quantity on 132 items meant $420 wasted plus a restocking fee. I now read the unit column twice. It sounds basic, but when you’re processing multiple orders in a day, it’s the most common slip.

Checkpoint: Read the unit: per item, per box, per case, per pallet? Confirm before clicking submit.

Step 6 — Verify Delivery Date & Location Requirements

Not everyone thinks about this, but it’s a big one for schools. If you’re ordering lab materials that require temperature-controlled delivery, or bulky art supplies that need a loading dock, the standard shipping option might not work.

In September 2024, I ordered Bacillus subtilis cultures for biology class. Standard shipping was three days. But it was a summer month here with temps over 90°F—standard ground could kill the culture. We had to upgrade to overnight shipping at the last minute, adding $23 to the order. That was the third such mistake. Now I always check: does the item need expedited shipping? Does it require a signature on delivery? Is the delivery address the correct building (not a central office that might hold it for days)?

Checkpoint: Confirm shipping method matches the fragility and timeliness of the item. Confirm the address is the location where someone will receive it.

Step 7 — Archive the Order Confirmation (With Notes)

I know, paperwork is boring. But this is where real savings come from. After the order is placed, I immediately save the order confirmation in a shared folder alongside a one-line note: “Ordered 20 bottle of isopropyl alcohol, 99% grade, for chemistry lab. Expected delivery Oct 15. Used promo code NASCOEDU2025 for 8% off, bringing total to $145.”

Why? Because when the shipment comes in wrong—and sometimes it does—I can quickly reference what I ordered, what I paid, and which promo code I used. It also helps if the item arrives late and we need to track it.

We’ve used this folder to resolve three disputes in the past year, saving about $200 in incorrectly charged fees.

Checkpoint: Take 30 seconds after purchase to note the order number, date, and any special terms. Future you will thank you.

Common Mistakes and What I’ve Learned

Even with the checklist, we still slip. A few things I’ve learned the hard way:

• Never assume standard sizes: Paper sizes vary regionally. 8.5 x 11 is US standard, but schools sometimes use A4 for international programs. I’ve mistakenly ordered US letter for an A4-only printer. That was a $120 reorder. (For reference: 300 DPI is standard for commercial print; 150 DPI is acceptable for posters.)
• Don’t skip the promo code step because you’re in a hurry: That’s exactly when a discount gets missed. I’ve lost about $200 in missed discounts in the past two years because I was rushing.
• If you think you don’t need a process, you need a process: We didn’t have a formal approval chain for rush orders until last year. Cost us when an unauthorized rush fee appeared on the invoice. Now we have a simple form.

This checklist isn’t perfect. But it’s saved our department time, money, and frustration. If you pick just two steps from this list—Step 2 (check inventory) and Step 4 (search for promo code)—I think you’ll see the biggest difference. Everything else is just layering discipline on top of experience.

Note: All pricing examples are based on actual orders from my department between 2019 and 2024. Verify current pricing with Nasco Education or your supplier as rates may have changed.