These blocks are a novel addition to water play, sand play, mud play, and outside play in general. Kids will enjoy making them and playing with them. They’re also pretty economical considering that a $4 bag of concrete mix will make quite a few blocks.
You can make these blocks in all kinds of shapes and sizes for a variety of play scenarios.
I like these blocks because kids can do things with them they’d probably never be allowed to do with expensive hardwood unit blocks. Concrete blocks are also pretty durable. I did some drop testing (repeatedly letting a block free fall onto a concrete surface from about 6′ in the air) and the only damage was some chipping around the edges. That said, they are not indestructible. But they should stand up to a fair amount of use and abuse.
- Concrete mix
- Mixing bucket
- Cooking Oil
- Trowel or mixing stick
- Disposable containers
- Utility knife
The process is pretty straight forward:
Mix It Up
In your mixing bucket, combine water and concrete mix as prescribed on the mix’s instructions. I usually aim for a mix with the consistency of egg salad or cottage cheese. Avoid soupy concrete.
Start out by wiping the inside of your containers with cooking oil. This will make them a bit easier to remove when the concrete cures.
The next step is to scoop your mix into containers. In my experiments, I tried containers ranging in size from mini muffin tins to half gallon ice cream containers.
Pack the concrete into the containers. You can use a stick or small trowel to smoosh it around–you want to remove any voids so you end up with solid concrete blocks.
Set Them Aside
Set your block forms aside to cure for about 24 hours.
Set Them Free
Once they’ve cured for about a day you can remove them from their container. The oil makes it easier to remove them, but it might not be easy. You might need to call on the help of a utility knife if they are really stubborn.
Help Them Cure
It takes concrete months and months to fully cure, so once your blocks are freed from their molds you’ll need to set them aside for at least a week before playing with them–two weeks would probably be better (A chance to practice patience!) Keeping them moist during this time can also make them stronger. You can set them in a tub of water like I did in the photo below, you can spray them with a hose every day, or you can let the kids paint them with water every day.
Time For Play
After a week or two of curing your new concrete blocks are ready to play. As mentioned above, these blocks play well with sand, water, and mud. The also get along well with stones, bricks, and all kinds of loose parts.
When I suggest this idea during training events, I sometimes hear worries about smashed fingers or toes. That’s something to watch out for, but in my experience kids don’t like to get hurt and quickly learn to handle these heavy blocks with care.
If you give this project a try I’d love to hear how it goes and see some photos. I can also answer questions–just pop them in the comments.
You also might be interested in this DIY Concrete Planter project.