Some students don’t fall behind.

They just… stop progressing.

It’s one of the hardest things to spot in a classroom - and one of the easiest to miss.

This week’s research looks at what might be happening under the surface when student growth quietly stalls (and drug use may be the culprit). And this week’s Tech Tool gives you a zero-prep way to keep early finishers engaged without losing your sanity.

You’re about to become an even better teacher in the next 4 minutes.

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And now, back to making you an even better teacher. ⬇️ 

BRAINY BIT

Cannabis use Matters - Your Students’ Brains are Still Under Construction

Here’s what the largest U.S. teen cannabis study means for your classroom.

TLDR: A landmark study of 11,036 kids aged 9–17 found that teens who used cannabis showed slower improvement (or flatlined completely) across 7 key cognitive areas, including memory, processing speed, and working memory, compared to non-users. 

The Study: Cannabis and neurocognitive development

Researchers used the Adolescent Brain Cognitive Development (ABCD) Study (the largest long-term brain study of kids in the U.S.) tracking 11,036 children across 21 sites from ages 9 to 17. 

What made this study unusually rigorous: cannabis use wasn't just self-reported. Researchers confirmed it using hair, urine, saliva, and breath toxicology tests. 

Self-report alone misses up to 60% of actual use (students aren’t always the most honest in reporting drug use for obvious reasons), so combining both methods gave a much more accurate picture.

Every two years, kids completed a full cognitive battery testing memory, processing speed, working memory, inhibitory control, visuospatial skills, and language. Researchers tracked how each child's scores changed over time, controlling for family history, other substance use, mental health, and background, making it one of the most thorough studies of its kind.

The Results:

Here's the twist: kids who eventually used cannabis actually started with slightly higher cognitive scores in late childhood. But by ages 15–17, the story flipped. Non-users kept improving across all 7 brain domains, while cannabis users' scores plateaued or fell behind (a pattern researchers call "restricted trajectory"). By age 17, working memory scores in cannabis users were measurably worse than controls.

A follow-up analysis using hair toxicology on 645 participants found that THC specifically predicted worse episodic memory by mid-adolescence. CBD-only exposure showed no significant difference from non-users, though researchers caution that many CBD products contain undetected THC.

In YOUR Classroom:

Us teachers are often the first to notice when a previously sharp student suddenly seems to stop growing academically, and this research gives that observation a neurological explanation worth knowing. 

Here’s how these results can impact your classroom approach this week:

Strategies That Work:

1. Watch for the plateau, not just the drop. Stalled performance across reading, memory tasks, or processing-speed activities can be just as meaningful as a sudden grade decline - flag it early.

2. Bring the science to your students. This study is a gold-mine for health, science, or advisory class - real data, real brains, real stakes. Teens respond to evidence, not lectures.

3. Build consistent low-stakes memory check-ins. Weekly retrieval practice (exit tickets, quick recall tasks) creates a personal baseline so you can actually spot when a student's trajectory changes over time.

The teenage brain is the most remarkable renovation project on earth - and this study is a strong reminder that what happens during construction absolutely matters. 

🚀 Noteworthy News

TECH TOOL

"I'm Done." The Two Words That Break Us.

Every teacher knows the creeping dread of a student finishing 20 minutes early and sliding toward the iPad like a heat-seeking missile. 

You have nothing ready. You feel too guilty for a movie or another unsupervised video game.

The Solution: Brainzilla

Here’s the answer - a completely free collection of logic, word, and visual puzzles that's actually challenging enough to hold attention.

Brainzilla lives entirely in the browser; no login, no download, no setup. It has dozens of puzzle types: logic grids, number games, visual patterns, and word puzzles spanning easy to intermediate difficulty. Enough variety that even the kid who "hates puzzles" finds something. 

Is This For YOUR Classroom?

One honest heads-up: it's free because it runs ads, and no one can control which ads appear. Your school's ad blocker will likely handle this, but preview it first on your network to be sure. Otherwise? Genuinely zero friction to implement. 

Also, this isn't a curriculum tool. Don't expect it to teach new concepts or replace extension tasks. It's a brain-engagement placeholder and nothing more (but that’s what makes it great).

Strategies That Work:

1. Early Finisher Station: Bookmark Brainzilla as the official "done early" destination so students always have a purposeful next step.

2. Class Warm-Up Puzzle: Project one logic puzzle on the board at the start of class and solve it together - silent, focused, zero prep required (also a great idea to leave for supply teachers).

3. Brain Break Bell: After a heavy work block, give students five minutes on Brainzilla as a genuine reset before the next task.

Brainzilla won't change the world, but it will survive your 2:45 PM on a Friday, and honestly that's enough for it to earn a spot in your teacher toolbelt.

WHAT DO YOU THINK?

We would LOVE to hear from you!

Reply to this email, or send us a message on Instagram! We’re here to walk with you in these crazy times!

Part of what makes The PEN Weekly community so special is the fact that our readers are teachers from around the world! We’re not going to lie, we think that’s pretty darn cool!

We’ll see you again on Monday 🍎

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