How many do you have? I usually have 5-7 at a time haha. I let them sleep in shifts.
I don't bother with high chairs.
Premake meals or use the banquet table from luxury party stuff for instant meals. They can help themselves.
Prioritize potty training. Once they are lvl 3 potty they will use it and less accidents means less having to bathe them.
Next prioritize thinking, if they have thinking skill level 3 they stop having nightmares.
If you also have babies, keep them in separate rooms. A baby crying will wake the toddler too.
If your toddler is independent they learn skills faster on their own. If they are clingy they'll learn them faster if a parent helps them.
Don't use tablets. They raise skills super slow.
Get a Blarrfy and have them babble to it over and over for super quick increases in communication
Have the toddler "watch" other Sims over and over for the quickest increases in Thinking.
Have the toddler "Play" with a teen or adult for the quickest increase in movement.
If one toddler is on the potty another can watch him/her for a small boost in the potty skill.
Toy blocks increase both movement and thinking (one at a time though)
Watching older kids do puppet shows increases their fun, attention, and imagination at the same time.
Keep fresh harvestables in their inventory for super fast meals. They also get a happy moodlet from eating them.