It would have been late 50s early 60s. I had a set of plastic blocks that connected together by snapping together. They were maybe 1/2 to 3/4 inch long. I remember the blocks as being white and the doors and windows etc were green. Could build hourses etc. The pieces went together like bricks. Was a great toy for the imagination. Does anyone remember that building set?

I had a two sets of such blocks (I actually still have one of them). One was red bricks with white doors and windows and longer white bricks for foundations. The bricks were about 3/4 inch wide and there there half bricks (4 interlocking points) or full bricks (8 points) and some longer. I believe Playskool made them.

I also had another set that sounds more like you describe with white bricks that were thinner and shorter. They had slightly raised tops for interlocking. Don't recall the mfg though.

Bottom line is Lego came out and dominated this market.

Thanks for the reply! Yes you have helped me better remember what they were and what you describe is exactly what I remember. Have a nice day.