Gravitrax Add-Ons

You may remember the boys having lots of fun learning with the Gravitrax track system from Ravensburger. Well the track can be extended indefinitely with extra track packs and add-ons – which are each sold separately (with sets costing £9.99 or £19.99). There is a Trax Extension Pack, Building Extension Pack, Action Catapult Add-on, Action Hammer Add-on, Action Loop Add-on and an Action Magnetic Cannon Add-on.Gravitrax Add-Ons loop

Gravitrax Add-Ons and Rollercoasters

Our boys absolutely love rollercoasters and we have visited many different theme parks (such as LEGOLAND Windsor, Alton Towers, Thorpe Park Resort, Chessington World of Adventures, Twin Lakes, Flamingoland, Paulton’s Park, Drayton Manor, Duinrell, Europa Park, Phantasialand, and Disneyland Paris). This has given them a good idea for what they like and inspired them so much that the teen is actually thinking about doing Engineering at University (and working on rollercoasters in Germany!). Although the Gravitrax system isn’t exactly the same as rollercoasters a lot of the mechanics behind it are the same – or gave us a good opening into discussions (which was really good because even the teen got involved).SWARM Coaster climb

The Gravitrax Add-Ons: Expansion Catapult

The Gravitrax Expansion Catapult makes sending balls flying over any obstacle possible. It can either be placed into the ground or the height can be varied by placing it on top of other tiles. You can either use some track to make the ball roll into the Gravitrax expansion catapult or you can place the ball in it. Likewise you can lock it down and press a button to fling it or you can manually adjust your angle to launch it from (which we found not to be as effective).Gravitrax Add-Ons catapult

The Gravitrax Expansion Catapult allows further development of STEM through trial and error, plus some discussion. We experimented with varying the height of the catapult: We wanted to determine whether the higher the balls are flung from has any effect on how high has and/or far they will travel to get over an obstacle. To see how far the ball went we measured it in terms of tiles it passed; and for height we built a tower that is crashed into, lower it a tile at a time to determine when it could pass. Of course the answer is yes – the higher you place your catapult the higher and further the ball will travel.

We also talked about the Gravitrax Expansion Catapult in terms of density – thinking about what would happen if the balls had been designed lighter. We came to the conclusion that they would not have travelled as fast or as far. This resulted us in thinking about weight restrictions on rollercoasters.

The Gravitrax Add-Ons: Action Loop Add-on

When it comes to rollercoasters the loops are probably are our favourites so Gravitrax Action Loop Add-on was perfect for discovering the mechanics behind them. What we gleamed is that we needed to work out how fast the ball (or a rollercoaster cart) needs to be in order to make it around the loop. If it isn’t going fast enough then it will not make it around the loop.Gravitrax Add-Ons Loop

With the Gravitrax tracks there’s nothing to hold the ball in so we need to adjust the speed accordingly. That the angle is dependent on the size of the loop and the height of the drop to keep it moving all the way through the loop. The steeper the gradient and higher the drop, the greater the acceleration. Rollercoasters are actually held in place by electromagnets, which regulate the speed of the cart and hold it in place – but it would still roll backwards. With the Gravitrax set the ball just caused the track to fall apart when the angle was too steep.

How fast the rollercoaster is going is worked out by working out the velocity – which is the change in acceleration over time. You work this out by taking the acceleration (which is the change in speed over time) and dividing it by time.

Note all scientific terminology has been provided by my teen and I take no responsibility for its accuracy!

We then put into practice what we had learned about rollercoasters using the Gravitrax add-ons by making our own out of junk materials.junk model rollercoaster

The Gravitrax add-ons are a great addition to the starter set and a great way of expanding STEM knowledge. They were great for thinking about things and using trial-and-error as well as thinking about them in terms of the real world (rollercoasters) and how we could use our knowledge to help design things for the future.


We received Gravitrax Add-ons Expansion Catapult and Action Loop Add-on for purposes of review. All opinions are honest and my own.

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