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How to Make Salt Crystal Hearts for Valentine’s Day

We love crystal experiments and one of our favorites has been making salt crystals. These crystals are low-cost and turn out perfect nearly every time! This Valentine’s Day, make your valentine these adorable salt crystal hearts! How are they made? Find out in this simple science experiment where you learn how to make salt crystal hearts.

Learn how to make salt crystal hearts with this Valentine's Day twist on salt crystals! It's a fun Valentine's Day science experiment.

We had so much fun making these Valentine’s day-themed salt crystals. One of our favorite things to do is to make seasonal versions of everyday science experiments.

It’s tons of fun and the kids ask to repeat the experiments every year!

How to Do the Crystal Heart Science Experiment

Try this fun Valentine’s Day themed science experiment and combine learning with the holiday of love.

Add this activity to your Valentines STEM activities!

Valentine Classroom Decorations

Add some Valentine’s Day festivities and flair to your classroom with these classroom decorations for Valentine’s Day!

valentine vibes classroom door decoration

Valentine’s Day Door Decorating Kit

love letter garland decoration

Love Letter Garland

valentines day classroom door tissue paper door decoration

Tissue Paper Classroom Valentine’s Door Decorations

valentines day window clings for classroom

Valentine’s Day Classroom Window Clings

happy valentines day classroom door decorating kit

Valentine Letters Classroom Door Decorations

valentine party classroom decor kit

Valentine’s Day Classroom Decorating Kit

our class is sweet classroom decorations

Our Class is Sweet Cupcake Valentine’s Day Classroom Decorating Kit

our love for learning grows classroom decoration

Our Love for Learning Grows and Grows Classroom Decorations

a class full of sweethearts valentines day decorating kit

A Class Full of Sweethearts Classroom Decorations for Valentine’s Day

Valentine’s Day Salt Crystal Science Experiment Explanation

When salt water evaporates, the water can no longer hold all of the salt molecules. When this happens, the salt crystals cling to anything nearby, including the rim of the jar and the chenille stems inside of the jar.

Over time, as the water evaporates, the salt crystals get bigger and bigger, making pretty, square crystals that are amazing to look at! Use a microscope to investigate these salt crystals up close for even more science fun!

What you’ll need to make salt crystal hearts:

crystal science worksheet

Valentine Science Books and More!

These fun Valentine’s Day Books for kids will teach kids about the science around Valentine’s Day, the history of the holiday, and a whole lot more!

the calendar kids meet february book

The Calendar Kids Meet February Book

valentines day math workbook

Valentines Day Math Workbook

in my heart a book of feelings

In My Heart a Book of Feelings

i love you around the world coloring kit

I Love You Around the World Valentine Coloring Book

valentine activity book

Valentine Activity Book

candy bites the science of sweets book

Candy Bites the Science of Sweets

holidays around the world valentines day

Celebrate Valentine’s Day Holidays Around the World

valentines day coloring book for kids

Valentine’s Day Coloring Book

hear your heart science book for kids

Hear Your Heart Science Book

cadiology for kids book

Cardiology for Kids Book

valentines day riddles book

Valentine’s Day Riddle Book

lego valentines day fun

Build Valentine’s Day Fun with LEGO

More Valentine Activities for Kids

Super Fun and Easy Crystal Science Fair Projects

Creative Valentine Engineering Challenges

Printable STEM Valentines for Kids

Valentine STEM Activities for Middle School

Llama Valentine Cards

Teaching Resources for Valentine’s Day

Here are some fun STEM teaching resources for Valentine’s Day that you can use in the classroom.

Browse the entire category of Valentine’s Day classroom supplies here or grab some of my Valentine’s Day favorites from the list below.

valentine build a bot

Love Bot Science Bots

learning resources pumping heart model

Pumping Heart Model

edible candy food science chemistry kit

Candy Chemistry Science Lab

yumology sweets lab candy science

Yumology Candy Science Kit

glowing candy lab science kit

Glowing Candy Lab Science Kit

exploding candy lab science kit

Exploding Candy Lab Science Kit

chemistreats classroom science valentine gifts

Chemistreats Classroom Candy Science Kits

lolipop lab science kit

Lollipop Lab Candy Science Kit

candy vending machine stem kit

Candy Vending Machine

candy perfume lab science kit

Candy Perfume Science Lab

lego roses

LEGO Roses

plasma heart

Plasma Heart

cross section heart model

Cross Section Heart Model

lego flower bouquet

LEGO Flower Bouquet

lego valentine heart bear

LEGO Valentine Heart Bear

cute valentine building block bears

Valentine Building Block Bears

valentine teddy bear kit

Valentine Bear Building Kit

clockwork heart building kit

Clockwork Heart Building Kit

lego friends flower and chocolate box

LEGO Friends Flower and Chocolate Kit

valentine lego card swans

LEGO Pop up Valentine Card with Swans

lego love birds

LEGO Love Bird Building Set

building brick lego candy shop

Building Brick Candy Shop

lego valentine wreath

LEGO Valentine Wreath

How to Do the Crystal Heart Experiment

For this Valentine STEM project, make salt crystal hearts for your Valentine’s Day STEM activities.

Fill your jars about 3/4 of the way full with water. Dump this water into a pot on the stove. Heat the water until it boils.

Slowly add salt into no more salt can dissolve in the water and crystals start to form on the surface of the water. Remove from heat.

This Valentine's Day, make your valentine these adorable salt crystal hearts! How are they made? Find out in this simple science experiment!

Fill the mason jars 3/4 of the way full of the salt water.

Bend a chenille stems  into the shape of a heart. Make sure the heart can fit through the mouth of the jar. Once the crystals form it will be hard to get it out of the jar if it is too big.

valentine stem challenges

Tie a string (or you can use another chenille stem) to the point of each heart. Use a clothespin to suspend the heart in the center of each jar.

This Valentine's Day, make your valentine these adorable salt crystal hearts! How are they made? Find out in this simple science experiment!

Set the jars in a sunny place and let the crystals start to form. The longer you leave them, the more they will grow!

We recommend leaving your salt crystals to grow for at least three days.

Take this further by comparing the size of crystal formation after 24 hours, 48 hours, 72 hours, and a week. How much bigger are the crystals after a week?

Carefully remove the crystals from the water and let them dry on a paper towel.

This Valentine's Day, make your valentine these adorable salt crystal hearts! How are they made? Find out in this simple science experiment!

Inspect the crystals with a magnifying glass or microscope. Each crystal has a rectangle shape!

Classroom-Friendly Valentine Shirts

I love wearing fun Valentine-themed shirts in the classroom during February. Here are a few of my favorite Valentine Shirts for Teachers.

be kind valentine teacher shirt

Be Kind Valentine Teacher Shirt

i love you sign language shirt valentines day

I Love You Sign Language Teacher Shirt

kindness teacher valentine day shirt

Kindness Teacher Valentines Day Shirt

heart teacher valentine earrings

Wood Heart Earrings for Valentine’s Day

teaching sweethearts valentine teacher shirt

Teaching Sweethearts Valentine’s Day Teacher Shirt

my class is full of sweethearts teacher shirt

My Class is Full of Sweethearts Teacher Valentine’s Day Shirt

heart tie dye shirt valentines day teacher shirt

Tie Dye Heart Shirt for Teachers

love all day every day teacher shirt

Love All Day Every Day Teacher Valentine’s Day Shirt

painted heart valentines day shirt

Painted Heart Valentine’s Day Shirt for Teachers

heart fraction math teacher shirt

Heart Fractions Math Teacher Valentine’s Day Shirt

heart penguin earrings for teachers

Penguin Heart Teacher Earrings

valentine alphabet teacher shirt

Valentine Alphabet Teacher Shirt

valentine note earrings for teachers

Heart Envelope Valentine Earrings

love sign language teacher shirt

ASL Sign Language Love Valentine ASL Teacher Shirt

all we need is love teacher shirt globe

All We Need is Love Globe Shirt

valentine kittens teacher shirt

Valentines Cats T Shirt

chemistry valentines teacher shirt science teacher

Valentine Elements Chemistry Teacher Shirt

sped valentine inclusioin shirt

Valentine SPED Teacher Inclusion Valentine’s Day Teaching Shirt

teacher conversation hearts shirt

Teaching Valentine Conversation Hearts Shirt for Valentine’s Day

this teacher loves her kids valentine shirt

This Teacher Loves Her Students Valentine’s Day Shirt

dinosaur love teacher shirt valentines day

Valentine Dinosaur Love Valentine’s Day Shirt for Teachers

Wearing a fun shirt, decorating the classroom with red and pink decorations, and doing other fun Valentine’s Day activities will make Valentine’s Day about more than just cardboard Valentines and candy.

Share this project with a friend!