For everyone who dislikes Curator, here's a maybe helpful tip:
Only one sim in the household needs to do most of the steps, then that sim can hand over their findings to the other family members and it will count for them, too. The only steps a sim needs to do by themselves is "send 3 (or was that 5)? objects to geo council" and "breed frogs 5 times".
For finishing a collection I find the pen pals/postcards one convenient, because the sim doing it doesn't even need to leave the house. With a toddler and a patch of sand in the backyard the seashells collection is finished quickly. Or any of the fossil/metal/crystal/my sims ones with a Scientist sim at their workplace.