I went to Mark Twain Elementary School from the 4th to the 6th grade, starting in the Fall of 1970. I enjoyed my years there and, I must say, it was a different atmosphere than that portrayed in the earlier reply to your message.
The principal for the first year was Dorothy Vukota and for the other 2 years was Frank Montoro (?). I had gone to Noriega Home School for 1st-3rd grades and moved on to Mark Twain for 4th-6th grades. I had a lovely teacher for 4th grade, Miss Sirosky. My favorite time in class was when we had to report on news articles we'd found in the paper. She had a mimeographed paper with "Who, What, When, Where, and Why" and we had to write something under each heading. I also took advantage of the music programs and took up the recorder and sang in the chorus. For 5th grade I had Mr. Johnson, a guy from the south who seemed rather out of place at our school. He was nice to me (I was always a good kid and learned my lessons), but if one acted up in class they were dealt with accordingly! It was in the 5th grade that I started violin lessons and played in the school orchestra under our lovely music teacher, Dorothy Clazie. My 6th grade teacher was Mrs. Frizbie. I had 3 good years at Mark Twain and have mostly fond memories of my time there. I'm trying to remember what the room numbers were for my classes. I think 4th grade was in room 4, 5th in room 5 and 6th in room 3. The rooms were on the upper level and if you exited the rooms and turned left there was a stairwell that went down and to the right of that, the library. Down the hall from the library were the kindergarten rooms, I think, and the cafeteria. I hope some others also have fond memories of Mark Twain!