Yesterday we were playing Plants vrs zombies. We were in "endless" mode and my oldest son was at the controls, my 5yo says that in the first waves you need to use the plants with the least amount of suns so that you can afford more of them. He says, "look, it's just subtraction over and over again! You need the ones that are worth the least amount and regenerate the fastest!" He went through a big long explanation of how each sun adds 25 and each of the plants subtract their amounts and how if you want to have lots of suns in the later stages you need to use the little stuff at the beginning! I'm so proud of him!!