The blocks are probably pine or other common softwood, but hollow. You can see the joints on the ends, and what looks like a top come loose in the background.

1942 Balsa would have to come up through sub infested waters from Caribbean or South American plantations, and what there was would go to airplane construction, either 1:1 scale, or flying models

The blocks seem to have wood grain under the paint. Yet, they must be fairly light, otherwise they would not be safe playthings for children of this age.

Judging from the wear on the corner of the block on the left, I surmise that these are made of Balsa wood, which was still abundant in that era. They might even be solid blocks of Balsa.

The little guy on his knees in the middle appears to be wearing what I knew as a safari jacket. It has a belt and big buttoned pockets and is short sleeved. It’s freshly pressed and he’s certainly styling.