Learn plant propagation and reduce the amount of money you spend on seedlings from the nursery. Many people look at the cost of the tiny seedlings and give up right then and there. 'It's cheaper to go to the supermarket and buy the food' they say. And they may be right. But it's possible to grow food on a budget, it might just take a little longer.
Starting seeds is fun no matter what age you are. Children learn valuable lessons about plant life and the rest of us squeal with excitement anyway when the seedlings emerge.
When you have some plants that produce particularly delicious food, why not try saving seeds? If your plant is a non-hybrid you should be able to produce an identical plant from the seeds unless there was cross pollination from a nearby related specimen. There are clubs which devote their time to seed saving and swapping.
Propagating cuttings from those plants which don't grow from seeds readily is another way of multiplying your efforts. You are effectively cloning and the resulting plant will have the same genetic makeup as the parent specimen. Often it's quicker and easier to treat woody plants this way. Snoop in the neighboring gardens and ask if you can have a cutting or three. In my mother's day it wasn't the done thing to ask...they just helped themselves! They used to joke that if it wasn't stolen it wouldn't grow. Don't try it now though.
Some plants benefit from division. Examples would be clumps of Lemongrass or Mint. Strawberries send out runners which can be kept and easily planted. Another form of division happens when one clove of Garlic becomes a bulb after a few months time in the soil. Potato growing also come under the heading of division. One tuber, or even a small piece, produce many more towards the end of its growing cycle.
I'm sure you can see there are many benefits to learning how to propagate plants.