Have kids view the following video of sexual reproduction in plants. Despite the great differences in the organs involved, have them note the cellular processes of meiosis and fertilization (segregation and recombination of chromosomes) are the same.
(Most of the technical jargon given in this video can be ignored but emphasize that meiosis occurs in the anthers giving rise to male gametes (sperm) within pollen grains. Meiosis, likewise, occurs within ovules giving rise to female gametes (eggs). The male gamete is delivered to the female gamete by growth of the pollen tube, and fertilization occurs. Germination and growth of pollen tubes can be see here: