Elbow and knee pads are not likely to be much use for a child on a scooter and I think are too restrictive to use on a bike - very small movements correct balance when riding so you need as unrestricted movement as possible. Once they are learning serious skating then they are of use.
Helmets MUST be fitted correctly. If possible go to an independent bike shop which are likely to be staffed by knowledgable enthusiasts rather than half trained teenagers on the minimum wage. A helmet that is loose is more dangerous than no helmet. It should be fitted straight across the forehead over the eyebrows and have the straps correctly tenshioned.
We took ds to our local cycle shop and they fitted him. I don't know the brand (and it's in his room so I can't check) but it should last him a few years. It's got a safety light on the back and he's definitely more comfortable in it than his first. Worth going somewhere and having some help, also got him to 'buy into' wearing it better. I suspect Evans cycles could also help?
We tried elbow/knee pads but they just restricted his movement which increased injuries!
The staff in halfords were very helpful when we wanted to get a helmet for our DS, and also our local Cycle King branch too, they let him try them on to get a good fit. Don't know about elbow/knee pads though, sorry.
DS 3 is now interested in learning to ride his bike and scooter and I don't know the first thing about choosing a helmet. What type of fit and safety features should I be looking for ? What brands are good?
Also is it worth getting knee and elbow pads or are they in practice of little use?
(did post in Toys and Games on SAT but nobody has replied) TIA