Why Flashcards for language learning work (+How to use them correctly)

Since the dawn of civilization, one invention has remained constant: the wheel. From wooden carts to Teslas, no matter how much technology advances, the core concept of the wheel remains unchanged—because it works. Some innovations are just that timeless.

Education has its own version of the wheel: flashcards.

Despite the rise of AI tutors, smart textbooks, and gamified learning apps, flashcards have stood the test of time. From prepping for your first spelling bee to cramming legal terms in grad school, many of us instinctively turn to flashcards when we need to memorize a lot, fast.

But why are flashcards so effective and how can you use them to study languages?

The Cognitive Revolution: Why Flashcards Work

Over 100 years ago, Hermann Ebbinghaus discovered the Forgetting Curve—a visual representation of how quickly we forget new information. Without review, most of what we learn fades within days.

But he also discovered something powerful: the Spacing Effect. When we space out our review over time, instead of cramming it all at once, we remember more for longer.

In the 1970s, Sebastian Leitner turned this insight into a system. Imagine five boxes: each flashcard starts in Box 1. If you get it right, it moves up and appears less often. If you get it wrong? Back to Box 1. The more you struggle with a card, the more you see it.

This simple idea laid the foundation for modern Spaced Repetition Systems (SRS).

What Are Spaced Repetition Systems?

SRS are algorithms that schedule your reviews at optimal intervals—just before you're about to forget. The idea is simple: stronger memories are reviewed less frequently, while weaker ones are reviewed more often.

These systems apply cognitive psychology in action, automating the spacing effect so you don’t have to guess when to study. Tools like Anki or Quizlet use adaptive learning technology to ensure reviews are personalized and efficient.

But Here’s the Catch: Students Don’t Always Use Flashcards Effectively

Research shows that many students misuse flashcards—or worse, rely on ineffective strategies like rereading or highlighting (Dunlosky, 2013). These methods feel productive, but often lead to overconfidence and poor retention.

Why? Because of something called Judgments of Learning (JOLs). These are our internal predictions about how well we know something. And they’re often wrong. For example, Kornell and Bjork (2008) found that even when spaced practice improved test scores, students still believed massed practice was more effective. The problem isn’t that students are lazy—it’s that our brains aren’t always great at judging our own learning.

How to Use Flashcards for Language Learning

If you're learning a new language, flashcards can be your best friend—or your worst enemy. Used right, they can build vocabulary, grammar, and even fluency. Used wrong, they can lead to wasted time and frustration. Here’s how to make flashcards work for you.

1. Choose the Right Platform

Not all flashcard apps are created equal. I personally recommend Anki, especially for serious learners. Why?

• It’s free and customizable

• It uses advanced spaced repetition algorithms (like FSRS)

• It has a massive library of premade decks for nearly every language imaginable

(Apps like Quizlet and Brainscape are great too, especially for beginners)

2. Design Your Flashcards the Right Way

It’s not just what you study, but how you structure the flashcard.

Highlight key info + Add Images – Bold or color code the word or phrase you want to remember or add images to remember things better!
Use mnemonics – If the Russian word for “milk” is moloko, imagine a cow saying “moooo-loko!”
Add context – Instead of just writing “chien = dog,” use a sentence: Le chien dort sur le canapé (The dog sleeps on the couch)

Why does this work? Because the brain remembers meaning, not isolated facts. The more vivid and connected your cards are, the easier they’ll stick.

An example of one of my Anki flashcards where I used an image and highlighted the word I needed to remember!

3. Embrace Desirable Difficulties

This might sound weird, but: make your studying a little harder.

Cognitive psychologists call this “desirable difficulty”—basically, if it feels a bit challenging now, it’ll stick better later. For flashcards, this could mean:

• Studying in random order instead of predictable sets

• Testing yourself before reviewing the answer

• Waiting longer between reviews, even if it feels uncomfortable

Example: Instead of flipping the card right away, try to write out the translation or say it aloud in a sentence. That mental effort makes the memory stronger.

4. Be Careful With Semantic Similarity

It might seem logical to group flashcards by theme—like a deck of fruits or body parts—but research shows that too much similarity can backfire.

When words are too closely related, your brain has trouble separating them. Mixing “apple,” “pear,” and “peach” on the same page? You might remember none of them clearly.

• Try to mix up your flashcard sets (instead of all colors or all fruits, combine them!)