Is your son interested in planes? You don't have to buy all the models you know :-) I found a site which shares free printables which will keep your little boys minds and hands busy and happy
This site is here
Go to the site i have shown and select a plane model you like.
download the template and print in heavy paper.
Then cut on the bold lines.
Fold on the dash lines. Refer to picture and assemble.
When Using glue use a glue stick.
hold with clothspin till dry.
Also...when you are using the plane outdoors coat it with spray paint thinly.