Unfortunately...it's not that simple. The January 22, 1986, daily strip (reprinted in "By Supper Possessed) shows Charlie Brown and Sally riding a school bus with the upper portion of the letters PINEC visible on the side of the bus. A few years later, in the January 8, 1990, strip (reprinted in "Make Way for the King of the Jungle"), this apparently new school name was verified, as Linus told Sally that they were (as usual) riding the school bus to Pinecrest Elementary School. So what happened? We do know, from her days of talking to her school building, that a horrified Sally once confronted the brick-strewn rubble that had been her school, after it quietly tumbled down. (It had "had all it could take.") For awhile, during the transition, Sally and everybody else apparently attended Peppermint Patty's school (where Charlie Brown wound up sharing a desk with the "rare gem," with limited success). Could it be that, rather than returning to James Street Elementary, they all went "back" to a different school, specifically Pinecrest? Nice thought...except that the tired school building "committed suicide" on January 9, 1976...which means that, five years later, the kids were already in James Street Elementary. And, so, the mystery remains: Why did they switch? Beats me, sports fans...
Just to make matters worse, in the television specials the kids attend Birchwood Elementary School. While the TV specials are not "canonical," this seems a needless bit of additional confusion...
http://www.fivecentsplease.org/dpb/peantfaq.txt
https://alt.comics.peanuts.narkive.com/yTvLf8pa/the-peanuts-faq-file