In a 152, OK. But do NOT try full flap in a Cessna 150.
As they left the factory, a 150 is a more capable soft field performer than a 152 - any flap setting. The 40 flap of a 150 will get the plane off the surface sooner, though the plane must be accelerated in ground effect before climbing at all. Generally, 150's had "climb" props (so greater thrush at slow speed) so got out well, and would climb with full flaps if required ('cause you blew the flap motor fuse). The 152 flaps were limited to 30, as I suspect Cessna no longer cared to have their trainer be like a bush plane. And, the 152 had a quite different prop, for better cruise. But, the cruise prop gave the plane lackluster soft field performance. My first experience taking 152's into grass runways I had commonly used in 150's was alarming. But, in fairness, Cessna did not design the 152 to so that. full flap takeoffs are not approved by Cessna, and if you got yourself in there to need that technique, you should have known better to begin with - as this pilot should. The adrenaline rush of a beach landing is briefly cool, but the risk of it going wrong is very high. Like snow, there are certain techniques in testing the surface, before you commit to landing there.