Mtb tyre for a junior rider

[Japie Nieuwoudt]

Hi all. 

I have a quesrion . What tyre and tyre size will you prefer for a junior rider doing schoolnseries as well as the trailseeker series . At the moment he have brand new Specialized renegades on . 2.2 x 29 front and back. Did one race with them and got a massive sidewall cut 7 km in the race. The tyres have 25 km on. 

What combination in size and tyre names will you prefer. He is 15 so the tyres must be lightweight as well. 

Thanks in advance