From clue 1, you can cross off 10 boxes: the intersections of hotel administration, Martha, and the lacrosse player; the two most recent grad years for Martha; the two oldest grad years for the lacrosse player; the oldest and most recent grad years for the Hotelie; and that Jennie is not the Hotelie.
From clue 2, you can cross off five boxes: Sibley is not Andrew, didn’t play basketball, and isn’t the engineer. The engineer didn’t graduate in ’86 and Sibley wasn’t in ’51.
From clue 3: Uris wasn’t the lacrosse player or the basketball player. Uris didn’t graduate in ’51 or ’62, Morrill didn’t graduate in ’51 or ’86, and Jennie didn’t graduate in ’74 or ’86. Also Jennie’s last name isn’t Morrill or Uris.
At this point, you know Stimson graduated in ’51. You can thus move all the information from 1951 onto Stimson: he’s not a Hotelie or a lacrosse player.
From clue 4: Stimson didn’t major in classics and his first name isn’t Ezra. Ezra isn’t the soccer player and he graduated in ’62 or later.
From clue 5: the tennis player graduated either in ’62 or ’74 and Andrew in either ’74 or ’86. Andrew isn’t an engineer, and the tennis player didn’t major in plant science.
At this point, Jennie and Martha had to have graduated in ’51 or ’62. Lacrosse and Uris could only have graduated in ’74 and ’86, so Jennie and Martha didn’t play lacrosse and their last name isn’t Uris.
From clue 6: Martha isn’t the basketball player, Andrew isn’t the lacrosse player, and the engineering major didn’t play tennis.
Now we know Ezra is the lacrosse player so we can transfer all the lacrosse player’s information to Ezra: he’s not a Hotelie, didn’t graduate in ’51 or ’62, isn’t Stimson or Uris.
Now we know Andrew is the Hotelie and his last name is Uris. Transferring all of the Hotelie’s and Uris’s info to Andrew and vice versa, it falls that Jennie is the basketball player, Andrew graduated in ’74, and Ezra in ’86.
Keep on transferring that data: Andrew Uris ’74, Hotel makes Morrill ’62 and Sibley ’86. If Jennie plays basketball, she is Stimson, so Jennie Stimson is ’51 and basketball and you can continue to transfer all the new information to all the associated traits. So we know it’s Martha Morrill ’62 and Ezra Sibley ’86.
We now know Andrew graduated in ’74. Going back to the clues, we know the tennis player graduated in ’62 (12 years earlier), so Martha Morrill is the tennis player and Andrew is the soccer player. Therefore the tennis player is the classics major, Martha Morrill. That means Ezra is plant science and Jennie is engineering. The rest of the answers fall out.
The final answers:
Jennie Stimson ’51, mechanical engineering, basketball
Martha Morrill ’62, classics, tennis
Andrew Uris ’74, hotel administration, soccer
Ezra Sibley ’86, plant science, lacrosse