PDF to QR code for teachers: share worksheets and answer keys

Upload the worksheet PDF on the PDF to QR code page, name the code after the subject and unit, tap "Create QR code", then place the code in a corner of the worksheet or on a slide. Students scan and open the file without a Google account or an access request. When you revise the worksheet, replace the file behind the same code. For answer keys, make a separate code and keep it paused until you release the answers. Files can be up to 10 MB, or 50 MB with a free account.

Steps

1. Save the worksheet as a PDF from the app you made it in, or scan a paper copy into a PDF with your phone.
2. Open the PDF to QR code page and choose the file.
3. In "QR name", type something students will recognize, such as "Grade 4 Math, Unit 3 worksheet". It appears as the heading on the page students see before opening the file.
4. Under Design, add a "Caption under the code" such as "Scan to open", then tap "Create QR code".
5. Keep the manage link, since you'll use it to replace the file or pause the code. If you sign up free and tap "Add to my account", all your codes live in one dashboard instead.
6. Download a PNG to drop into your worksheet or slides, and test a scan from a real printout.

Students see a qrfast file page with the code's name, the file type and size, and "Open file" and "Download" buttons. That page shows an ad, which keeps the service free, so it's worth knowing before you use it with a class.

Compared with sharing a Google Drive link

Drive works well when the settings are right. These are the settings to get right:

• Access: under "General access", choose "Anyone with the link". While it says "Restricted", only people you've given access can open the file (Google's steps).
• School accounts: Google notes that if you use a work or school account, you might not be able to share files outside your organization, and the sharing options depend on the account type.
• Your name and email: Google notes that when you share a link to a file, your name and email are visible as the owner. A qrfast file page doesn't show your email, but downloads keep the file name you uploaded, so give the file a clean name before uploading.
• Replacing the file: Drive keeps the same link if you use More, "Manage versions", then "Upload new version" on a computer (Google's steps). Uploading it as a new file gives it a new link, and the old QR code keeps opening the old file.

If you can set Drive permissions and don't mind showing your email, Drive is fine, and you can still make a website link QR code that points to the Drive link so you can change it later. Uploading to qrfast suits you when students should simply scan and read with no permission issues. The limits: PDF and images only, files up to 10 MB (50 MB for members), an ad on the file page, and no version history, because the old file is deleted when you replace it.

QR size on A4 paper and slides

• A4 worksheet: students scan from close up, so a code 3 to 4 cm (about 1.5 in) wide in a top corner or at the bottom of the page is enough. Leave a blank margin at least four modules wide around it.
• Photocopies: copies of copies blur the pattern. Use a black code on white with no light colors or gradients, and test a scan from an actual copy before copying for the whole class.
• Slides: a common rule of thumb is that a code should be at least one tenth as wide as the scanning distance. If the back row sits 6 m from the screen, the code should be about 60 cm wide on screen. On a typical projector screen, that means making the code roughly half the height of the slide. Test from the back row before class starts.
• Image file: download a PNG at 1024 or 2048 px, or an SVG, so the code stays sharp when enlarged on a slide.

Replace the worksheet with a new version

1. Open the worksheet code's manage link, or its page in your dashboard.
2. In the "File" section, choose the revised file under "Replace file".
3. Tap "Upload new file".

The new file is virus-scanned first. During the check, anyone who scans sees a note that the file is being scanned, so don't swap files while students are scanning in class. The old file is deleted at once, so keep your own copy. Students who downloaded the old version still have it on their phones, so ask them to scan again after a revision.

Release answer keys on schedule

1. Make a separate code for the answer key and give it a clear name, such as "Grade 4 Math, Unit 3 answers".
2. On that code's manage link, tap "Pause". Anyone who scans now sees a page saying the code is paused.
3. Print the answer code at the bottom of the worksheet. When it's time, tap "Resume" and the same code opens the answers.

Once the answers are open, students can download or forward the file. Pausing again doesn't remove copies already on their phones.

FAQ

Can I upload Word or PowerPoint files?

Not yet. Save them as PDF first. For slides, save the whole deck as one PDF.

Can I see how many students opened it?

The manage link shows how many times the file page was opened and what share of scans went on to tap "Open file" or "Download". It doesn't say which student, and one student scanning twice counts twice. To track who handed in work, use your class's assignment system or a separate form.