Letterbox Lab – Investigate Box 3: Magnetoslime

Letterbox Lab provide innovative children’s science kits as subscription boxes.

The Explore Box (£8 + £2 postage) is for kids aged 6+ and contains a least an hour’s worth of fun science.

The Investigate Box (£22 + £2 postage) has more experiments and more items of collectible lab equipment with enough to keep a junior scientist busy for 3 or 4 hours.Both kits have full-colour illustrated instructions and online videos to make it easy to do all the experiments. My eight-year-old is trying out the Investigate Box!

The box is fairly large, but with any luck should still fit through your letterbox!

This month’s theme is Magnetoslime, and there are seven experiments in this month’s box.

There are some really cool things included in this month’s box, including magnetic slime and Buzzmagnets! 

The first experiment is making Slippery Slime. It’s pretty simple to make with the ingredients included, and slime is always fun!

This is also interesting because it’s a non-Newtonian fluid, which means it hardens under pressure. Very gloopy and entertaining!

The Marble Mystery is a marble in a tube of sand, and you have to figure out how to get the marble from the bottom of the tube to the top.

We did manage to do this! It doesn’t tell you how in the booklet, though you do get a clue. It’s surprisingly satisfying figuring it out.

Here are the Buzz Magnets and Magnetic Slime.

Playing with magnets is always great fun, and these are really good one! They are called Buzz Magnets because they make a kind of buzzing noise when the snap together.

The slime works more like traditional slime, and there are several suggestions for using it.

One is to make it into an arch and see how long it stands up for. You can also use the magnets on it.

Magnets are also used for making patterns with iron filings, which are also included.

The Cloud in a Bottle experiment is really quite beautiful.

The moving swirls look wonderful, and using the magnet and iron filings to change the patterns is a lot of fun!

As always, the experiments in this box are incredibly involving, and the results are interesting to observe. Slime is always going to be a favourite of children, both making and playing with it, and they enjoy getting a little messy too!

The magnets and slime are lovely things to have and play with, there’s a great deal to be said for keeping things low tech! Kids can do lots of experiments with magnets, and these ones are really strong so are very effective.

This month’s box contains your first certificate of achievement and also a little bonus gift:

It isn’t an experiment, but it’s really fun! It’s a plastic dinosaur encased in a plaster rock, with a couple of tools to dig it out and play archaeologist!

Letterbox Lab always gives great entertainment value and value for money. The experiments are clearly explained, and the illustrations are great fun.

I particularly like the items to keep this month, the magnets and slime have given us a lot of fun already, and it’s a great way to combine experiments with play.

There is a lot to learn here, and they are things that will also come up in science learning at school, as well as thinking about how they apply in the real world. Children are also encouraged to be curious and ask questions about the things they’re doing, guided by the instructions.


Our score: 9.6/ 10

A wonderful way to introduce children to proper scientific principles and method, while keeping them engaged and having fun with science!

  • Quality of products10
  • Originality9
  • Packaging and delivery10
  • Value for money10
  • Selection of products9

How would you rate Letterbox Lab ?

Rating: 3.1/5. From 48 votes.
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