Not a curriculum, but I bought my kids lots of educational games.
Cluefinders adventures are awesome! I know they have 3rd through 6th grade not sure about 2nd.
I don’t remember which ones were good and which ones weren’t. But it’s what holds our kid’s interest.
My daughter was tested when she entered kindergarden and was reading at the third grade third trimester level.
My daughter scored 35 on the ACT and my son 34. Both had full tuition scholarships.
From then on, the last official project our kids did was researching books and writing their own curriculum and submitting it to the district office.
We used mostly books from the 1830s to 1860s, far more advanced and more efficient and logical than modern junk.
Daughter tested by district assistant superintendent when she was in third grade and found to be somewhere higher than second year college level in reading and comprehension.
We did Scrabble for spelling and Yahtzee for math.
There are many games that teach critical thinking skills.