Looking for easy, homemade World Book Day costumes? This step-by-step DIY Mr. Men costume tutorial will show you how to create a Mr. Happy costume and a Mr. Strong costume using simple materials.

These costumes are budget-friendly, fun to make with kids, and perfect for school dress-up days.

I absolutely love a homemade costume, and so do my kids. Whenever their school announces a dress-up day, they rush to our book collection, pick their favourite characters, and we start planning. Making costumes by hand isn’t just a great way to save money, it’s also a fantastic family activity. Over the years, my boys have always helped with their costumes, from cutting and gluing to painting and adding finishing touches. It makes World Book Day even more exciting, knowing they have created something unique.

Please follow me on Instagram @MotherOfGrom to see this years World Book Day costumes

A few years ago the school set a 'Mr Men' theme, so we decided to make costumes of Mr. Happy and Mr. Strong, two of the most recognisable and loved characters from Roger Hargreaves’ classic Mr. Men series. Their bold colours, simple designs, and cheerful personalities make them ideal for an eye-catching, homemade costume that stands out in the classroom.

I just want to note that most of these materials were items we already had at home when making the costumes, but I have linked everything we used. When it comes to spray paint, I highly recommend Kobra Spray Paint - we’ve tried many different brands over the years, and this one always provides the best coverage. While the initial cost may seem higher, I’ve found that cheaper alternatives often require twice the amount to achieve the same result, making Kobra the better investment in the long run.

If you love making your own costumes, you can check out all my other homemade costume ideas for children and teachers here.

DIY Mr. Strong Costume

Mr. Strong is one of the most iconic Mr. Men characters, known for his bright red square-shaped body, big smile, and signature green hat. This homemade costume is easy to create using household materials.

Materials Needed:

• Cardboard box (big enough to fit over your child’s torso)
• Black mesh sheets (for the eyes)
• Sticky-back black felt (for the face details)
• Kitchen roll tube (for the dumbbells)
• 2 balloons (for the dumbbell ends)
• PVA glue
• Newspaper (for paper-mâché)
• Foil (for the hat shape)
• Green acrylic paint (for the hat)
• Red sweatshirt
• Red joggers
• 2x Kobra HP Spray Paint - Matt Finish, Acrylic, 400ml in Venom Red
• 1x Kobra HP054 400ml Aerosol Spray Paint - Satin Black

To start, find a cardboard box that fits over your child’s torso and cut out eye holes and armholes to ensure they can see and move comfortably. To make the costume sturdy, reinforce the entire box with layers of paper-mâché using PVA glue and strips of newspaper. Allow each layer to dry before adding another for durability.

Once the box is completely dry, take it outside and spray paint it red using a matte acrylic spray. It’s best to do this in a well-ventilated area while wearing a protective mask. Allow the paint to dry completely before moving on to the next step.

To create Mr. Strong’s dumbbells, blow up two balloons and tape them to either end of a kitchen roll tube.

Cover the entire structure with paper-mâché to give it a solid shape. Once dry, spray paint the dumbbells black and leave them to dry completely before handling.

For the face, cut out the signature Mr. Strong smile from sticky-back black felt and carefully position them on the front of the box. Clue the black mesh sheets inside the box to enable your child to see out.

The final touch is his green hat. To make this, shape a hat out of foil, cover it with paper-mâché for extra strength, and then paint it green. Once fully dry, attach the hat to the top of the box using hot glue.

To complete the costume, dress your child in red joggers and a red sweatshirt. Let them carry the homemade dumbbells for the full Mr. Strong effect. This costume is lightweight, eye-catching, and perfect for an energetic, fun-filled World Book Day.

DIY Mr. Happy Costume

Mr. Happy is one of the most loved characters in the Mr. Men series, recognised for his bright yellow round body and ever-cheerful smile. This costume is lightweight and easy to make, ensuring comfort for your child throughout the day.

Materials Needed:

• Giant balloon
• PVA glue
• Newspaper (for paper-mâché)
• Sticky-back black felt (for the facial details)
• Kobra HP100 400ml Aerosol Spray Paint - Yellow
• Yellow cap
• Yellow sweater
• Yellow leggings

Start by blowing up a giant balloon and balancing it in a pan or colander to keep it steady while working. Cover the balloon with paper-mâché, applying at least four layers for strength. Allow each layer to dry for 24 hours before adding the next.

Once fully dry, take the balloon outside and spray paint it yellow. Two coats will ensure an even, vibrant finish.

When the paint has completely dried, pop the balloon inside the shell and widen the hole at the bottom so your child can fit inside. Carefully mark and cut out holes for the head and arms, making sure they are positioned correctly before cutting, as once removed, the paper-mâché cannot be replaced.

For the face, cut out the eyes and mouth from sticky-back black felt and attach them to the front of the costume. To add an extra fun detail, write “Happy” on a yellow baseball cap using black felt letters.

To complete the look, dress your child in yellow leggings and a yellow sweater. The result is a lightweight, eye-ctaching costume that brings Mr. Happy’s cheerful energy to life.

‍

Creating these costumes is also a great way to get your children involved in the creative process. Handmade costumes allow kids to feel proud of what they have made, and it’s a wonderful bonding activity that adds excitement to World Book Day.

If you’re looking for more handmade costume ideas, check out all my other World Book Day costumes for children and teachers here.

I’d love to see your creations - let me know if you try these costumes on Instagram @MotherOfGrom It always makes my day when people send or tag me in their creations!