Contrast Engine
ArticMinimal / Multiple / Maximal Oppositions
Vochella collapses practice into three scalable, evidence-backed game families. Play the core games below — live, right in your browser — and see how difficulty scales without a dozen duplicate mechanics.
Take the 90-second tourNow playing: Contrast Engine
Minimal / Multiple / Maximal Oppositions
The gallery
Tap any tile - they all run live right here. Legacy mechanics are archived behind these three scalable game families.
Minimal / Multiple / Maximal Oppositions
Complexity-Target Motor Practice
Caregiver Training Home Practice
Coverage at a glance
The matrix below shows which games cover which clinical domains. Tinted cells indicate an evidence-based fit; numbers show how many protocol exercises currently ship for that pair.
| Domain \ Game | Contrast Engine | Articulation Drill | Parent-Coached Loop |
|---|---|---|---|
Articulation 14 exercises | · | ||
Receptive Language 8 exercises | · | · | |
Expressive Language 11 exercises | · | ||
Fluency 6 exercises | · | · | |
Voice 5 exercises | · | · | |
Pragmatics & Social 5 exercises | · | · | |
Swallowing 7 exercises | · | · | |
Cognitive-Communication 5 exercises | · | · | · |
Literacy 7 exercises | · | · | |
AAC 5 exercises | · | · |
Practice Library
Browse all 73 activities in the Vochella practice library. Switch views to see how kids experience each exercise or review the clinical details.
See the picture. Say the word. Flip the card for a helpful cue. Then say it again, nice and clear!
See the picture, say the word, then flip the card!
Practice words that start with S sounds - like spider, snake, and star! Say each word clearly and try putting them in a sentence.
Say the ssssnake words! 🐍
Listen carefully to two words that sound almost the same. Can you hear the difference? Pick the right picture!
Listen carefully! Which picture matches? 👂
tea
key
Listen to a bunch of words with the same sound, then try saying them yourself! We'll keep practicing until you're a pro.
Fun exercises to make your tongue and lips stronger! Try tongue taps, side-to-side sweeps, and funny lip shapes.
Practice saying longer words piece by piece! Start with the ending and build up - like putting blocks together.
Practice saying helpful phrases like "I want...", "Help me", and "More please" - words you use every day!
Practice your TH sound! Try words like "think" and "this" - put your tongue tip gently between your teeth.
Listen to two words that have very different sounds. Can you say both? Try to make each one sound clear!
mop
top
Climb the ladder! First say the sound, then a syllable, then a word. You level up every time you nail it!
Say S sounds step by step - sound, syllable, word! Your speech buddy cheers for each level.
Climb the L ladder with your speech buddy - one rung at a time!
Practice your TH sound one step at a time!
Say SH sounds step by step!
Can you do two things in a row? Listen carefully and follow the steps! Touch your nose, then clap your hands.
Can you do what I say? Listen carefully! 👂
Look at the picture and answer questions like "Who is that?" and "Where are they?" Pick the right answer!
Who is in the picture? 🖼️
Which one is a fruit? Which one is an animal? Sort things into groups and find which one doesn't belong!
Which one is a fruit?
Can you follow 3 or 4 steps in a row? This is a big-kid challenge - listen carefully and do each step!
Be a detective! Look at the clues in the story or picture and figure out what happened. How do you know?
Listen to a short story and then answer questions about what you heard. No peeking - just your ears!
Tap or drag - is it an animal or a food? You earn stars for every correct bin!
Think about what grows and moves - does it breathe? Sort carefully!
Read a story, then tell it back in your own words! Who was in it? What happened? How did it end?
Look at the picture and make up a sentence about it! Try to make your sentences longer and more interesting.
Try adding more words! If you said "dog run," try "The big dog is running fast!" Make your sentences grow.
Can't think of a word? Use clues! What group is it in? What does it look like? What does it do? The clues help you find it!
Look at the before and after pictures. What happened? "He walked." "She played." "They painted!" Add the -ed ending.
Practice real conversations you use every day - like ordering at a restaurant or calling a friend. Repeat until it feels easy!
Think of action words like "eat" or "drive" - who does it? What do they do it to? Answer questions about each action.
Put the words in order to tell what is happening in the picture!
Build a sentence about what already happened. Don't forget the -ed!
Pick the right pronoun and build the sentence!
Put the pictures in order - morning to night! Then tell the story.
Start your words softly and smoothly, like a quiet sigh. Begin with easy words and build up to sentences!
Try bouncing on words on purpose - it helps you feel in control! Start easy and work up to real conversations.
If you get stuck on a word, stop, relax, and try it again smoothly. It's like a do-over!
If you feel stuck in the middle of a word, gently ease out of it and finish smoothly. You've got this!
Have a fun chat with your parent for 10-15 minutes. They'll cheer you on for smooth speech!
Say sounds with a gentle, light touch - don't push hard! Practice letters like P, B, T, and K softly.
Put your hand on your tummy and breathe in deep - feel it expand! Then say "ahhh" for as long as you can.
Warm up your voice with four fun exercises! Hum, glide your voice up and down, and hold notes. Do it softly.
Start by humming softly and feel the buzz on your lips! Then try humming into words and sentences.
Say "AHHH" as loud as you can and hold it! Think LOUD. This helps your voice stay strong and clear.
Make sounds through a straw! Try blowing bubbles in water while humming. It's fun and great for your voice.
Swallow as hard as you can - squeeze all your muscles! Start without water, then try small sips.
Put your hand on your throat, swallow, and hold the top for 3 seconds.
Follow the steps: breathe in, hold it, swallow, then cough. This keeps things going the right way!
Stick your tongue gently between your front teeth and try to swallow. Only practice without food or drink!
Lie down flat and lift your head to look at your toes. Hold it, then rest. Repeat to build strength!
Put a ball under your chin and press down. Hold for 5 seconds, then relax. This builds swallowing strength!
Press your tongue against the roof of your mouth as hard as you can! Try the front, sides, and back.
Practice paying attention! Start with one thing, then try focusing even when there are distractions around you.
Remember a piece of information and try to recall it after longer and longer waits. How long can you remember?
Practice making a plan! Break a big task into steps and put them in order. What comes first? What could go wrong?
Something went wrong! Think of solutions, weigh the pros and cons, and pick the best one. Talk through your plan.
What happens first, next, then last? Arrange the pictures and tell what happened!
Find words that rhyme - cat, hat, bat! Can you think of more? Sing songs and sort rhyming words together.
Break words into tiny sounds - c-a-t! Then put the sounds back together. Use the boxes to help you count.
See a letter, say its sound! S says "sss", T says "tuh". How fast can you go through them all?
Read together and talk about what you think will happen next! Make pictures in your mind and connect the story to your life.
Drag the letters into the boxes to spell the word. The picture helps you out!
Build words with two sounds at the start - like FR in frog!
Add the magic E at the end - it turns short vowels into their long names!
Practice the words you use most - "more", "stop", "go", "help"! Tap each word on your device as you say it.
Watch and listen as a grown-up points to words while talking during play. You'll start using them too!
Hand over a picture to ask for what you want! Start simple and build up to making full sentences with picture cards.
Add new words to your device - food, people, classroom things! Practice finding them quickly so you can use them anytime.
Combine words to say more! Try "want + cookie" or "go + park". Practice the same button path each time so it becomes easy.
This catalog is a snapshot of exercises available in the Vochella practice library. Click “Preview” to see how kids experience it, or “Feedback” to share your thoughts.
The science
We don't gamify therapy for novelty — we gamify because motor learning and language acquisition require massed, distributed, and motivating practice. Each game below traces back to a protocol or line of research.
Minimal / Multiple / Maximal Oppositions
SLPs assign contrast sets by process, field size, locale, and production phase. The same engine scales from a 2-option minimal-pair perception task to a 6-option maximal-opposition probe with speech recording.
Minimal pairs fit mild cases; multiple and maximal oppositions better support broader phonological-system change.
Storkel, 2022; Gierut complexity approach
Complexity-Target Motor Practice
A single drill family replaces flashcards, mic recording, sound ladders, and picture naming. SLPs tune target phoneme, stimulus level, complexity bias, cue start, and probe cadence while the engine only proposes changes for clinical review.
Complex, marked, and non-stimulable targets can drive wider generalization than simple stimulable targets.
Motor learning; Storkel, 2018
Caregiver Training Home Practice
The home-practice loop is built around caregiver training, not child-only app time. SLPs assign a technique, routine, duration, cadence, and capture mode; parents submit a short recording or log for review.
Recent home-practice evidence centers on structured parent-implemented intervention and caregiver training.
Zwitserlood-Nijenhuis et al., 2023; Leafe et al., 2025
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