We have leftovers very often for lunch. When I make lasagna, spaghetti, enchiladas, mac and cheese and many other entrees, I freeze leftovers in portions or make small portions as I make the large dish and freeze them right away. I have several sets of pyrex dishes, I bought them from Sam's Club. They come with flexible lids, they can all be baked or frozen. The small rectangle ones are good for single servings.
So meal ideas...
Make extra meat spag sauce, I make huge batches in the crock pot. Freeze in individual baggies for lasagna, spaghetti or the best lunch option, sloppy joes. This is great on thick slices of homemade bread toasted.
Crock pot pinto beans, cook with plenty of spices. Mash partially with potato masher or use a food processor on pulse. Freeze portions for mexican dishes in plastic bags or make ahead individual/family servings of enchildas and freeze. Mix with taco seasoned ground meat and make quesadillas. Dip in sour cream, salsa and have tomatoes and lettuce on the side.
Mix cornbread batter and slice hotdogs. Slice the same number of hotdogs as you want muffins IE 12 muffins, 12 sliced hot dogs. Use healthier kosher hot dogs, and use spelt/whole wheat/quinoa flour in the cornbread mix for a healthy option. Bake as normal. I freeze the extras and take them out and defrost for a quick lunch. I serve them with fruit or veggies raw.
Leftover pot roast, beef or pork on sandwichs.
I make almost all of our food homemade. This year Nathalie is doing more and more of the meals, she can cook quite a few of the things that I can. She can use the lower oven to put things in, but cannot take them out yet. She is 7 and by the time she is 9 or 10 I want her to be fully capable to run the entire kitchen. She can already clean it top to bottom, load and unload dishes, work with knives, use the cooktop and she can make bread from start to finish. Both of the kids are good at these things, though Tad prefers to be stacking and splitting wood, fencing, snow shoveling, working in the shop. Nathalie has to learn these things as well but she will be most proficient at cooking, sewing and cleaning.
Society tells us that males and females should be identical in abilities and jobs. But I see that isnt true just with my two kids. I raise them equally, they both have to learn all chores. But I see how much he prefers the "manly" stuff and she loves the 1800's idea of a woman.
Have fun cooking!