As with any board choice Sausage it'll depend on height and weight. I spent a fair bit of time searching for the right one for my middle child because he wanted one he could carry and duck dive. The majority of his peers have boards that are wide and thick and this was certainly a major factor for me but he finds it difficult to submerge the board and get out the back. I sacrificed that aspect to get a board that is stable, floaty and turns without too much strength required. I also went with a stringerless epoxy with carbon rails, mainly for durability. Checkout
to view how the board goes, you will see a Merrick pod that was second hand for 300 bucks that goes well for a 8 year old and also a 4'6 custom that a 5 year old shreds on! (blue vest), my bloke is in yellow and is riding a 5'3 Aloha, you can get them on ebay but they are pricey (590 for that one)