I am going to give you the rough amounts that I use to make 2 pans of lasagna that are 9x13 in size. I don't go by exact recipe amounts unless I am baking. That is just the way I learned to cook.
3 - 3.5 lbs. of ground beef - brown in a large skillet with 1 large onion, finely chopped
Add 4 cans of sauce (or your own homemade if you are a saint)!
Add 1 or 2 Tbsp of white sugar and simmer on low. If it gets 2 thick, add a little water.
Ricotta mixture - in a mixing bowl combine:
16 oz of ricotta
salt, pepper and parmesan to taste
You also need
9 cooked lasagna noodles per dish (18 total) - I always cook a few extra
shredded mozzarella - 1-1.5 lbs per lasagna (2-3lbs total)
Spray the bottom of each pan with pam and layer in the following order:
Ricotta (1/6 of the mixture-just eyeball it)
Sauce again (you need sauce between the last layer of ricotta and mozzarella)
Each pan will have 3 layers of noodles, 3 layers of ricotta, 3 layers of mozzarella and 4 layers of sauce. Try and plan accordingly when you are dividing up the ingredients.
I bake a thawed out lasagna, covered in foil, at 325 for about an hour and a half. The last 10-15 minutes I remove the foil so it browns a little bit. Let rest for 5-10 minutes before cutting.
My mom went to work 2 days a week when I was in high school and I cooked, or at least started supper on those nights. I didn't mind at all and liked cooking right from the start. She was able to call me from her work and talk me through getting dinner started over the phone. As a result, it was more coaching by her verbally, than actually showing me. Perhaps that is why I don't really measure and just kind of make it work. You don't need to be a math teacher (like nerdy little me - lol) to figure out how to divide the ingredients up! Just run with it. If you are really concerned about having enough ingredients, buy a little extra mozzarella and a jar of extra sauce in case you need it. If you don't need it, you will still have it on hand for another meal.
Cooking is individual. I used ground beef, you might make meatless or add sausage or a combination of meat. I add a little sugar to my sauce and you could skip that. I like the ricotta thinned with egg, you might like chunks of ricotta. Lasagna can be made a million different ways and still taste good. Tweak it to your taste.
Frugal notes - try to stock up on ingredients when they are on sale or at least buy the cheese and sauce at a warehouse club in bulk. I bought 9 cans of sauce at 99 cents each, but had I picked it up the last time I was at Sam's club, I could have bought a jumbo container of sauce.
Can you see how OCD I am from this picture of a shelf in my freezer? I have to have all Pyrex dishes with glass lids so they stack neatly. Honestly, it bugs me immensely that they are not all the same color. Buying those dishes actually has saved me a lot of money. A few years ago I had coupons for $3 off any Pyrex. Walmart had sets with a 9x9 and a 9x13 for about $15 less the $3 coupon and I invested in a few sets. I have used those dishes over and over for freezer meals which ends up being way cheaper than throw away pans from the dollar store over time. I would hate to go to all the trouble, use a flimsy foil pan and have a fiasco! You could also pick up dishes at a thrift store, but you aren't likely to find them with lids which saves on the need for foil.
Do you know what is to the left of the Pyrex on the same shelf? Another freezer secret... Boneless, skinless chicken that was purchased on sale. I cut it into bite sized pieces sautéed it with onion and then portioned it into small freezer bags. Ready to go for a quick dinner on the fly. I do the same thing with ground beef. I buy it on sale and cook it with onion before I freeze it. You can make tacos in about 5 minutes with precooked ground beef and that is exactly what we did last night!
This is the first time I ever made 4 lasagnas at once. I used to do 2, then I upped it to 3 and this time I made 4. I don't see ever going beyond 4.