根据您的问题，我找到了一些关于离别的英语诗歌，这些诗歌虽然不是专门为小升初而写，但它们表达了离别的情感，非常适合用在小升初的场合。以下是一些精选的诗句：

1. 珍惜每一次相聚的时刻
   “No matter how long the future holds, cherish every moment we meet; no matter how many springs, summers, autumns, and winters, we are forever good friends.”

2. 友谊的缆绳
   “Waving goodbye, setting sail, I can’t forget the rope of friendship you threw, invisibly tying firmly to my heart.”

3. 幸福的刻痕
   “Docking at the harbor where the clouds rise, secretly carving happiness on your heart, binding us tightly with a thread of friendship at the end of time!”

4. 时光的流逝
   “Years flow by easily, time casts us aside, but I have thousands of blessings to accompany you on your journey, may you walk well.”

5. 友谊的珍贵
   “When we meet, we don’t know the value of friendship; it’s only when we part that we realize it’s the most needed thing in life, like salt, without it, what flavor is left?”

6. 离别的惆怅
   “A steam whistle falls in the wilderness; boundless melancholy and loneliness, at the moment of parting, sprout together from the heart.”

7. 别离的话语
   “There are so many things to say at parting, a thousand words turn into one, don’t forget me.”

8. 别离的祝福
   “Tears of parting add new waves to the river of memory; blessings of parting open the curtain for another reunion.”

9. 离别的哲思
   “Since we are not looking back, why remember? Since we are not destined, why swear? Today’s events, like water without a trace, what will tomorrow be? You are no longer a stranger.”

10. 未来的祝福
    “Tomorrow we part, but may the clouds and the sun always accompany you to the farthest horizon; may flowers and green grass follow you as you spread your journey far and wide.”

这些诗句表达了对离别的不舍和对未来的美好祝愿，非常适合用在小升初的场合。希望这些诗句能够帮助您表达对同学和老师的离别之情。

‌小升初离别的英语诗是《别离辞:莫悲伤》（A Valediction: Forbidding Mourning），作者是约翰·多恩（John Donne）。‌

这首诗表达了离别时的深情与豁达，原文如下：

As virtuous men pass mildly away
正如贤人安然辞世
And whisper to their souls to go
轻声呼唤灵魂离去
Whilst some of their sad friends do say
悲伤的有人或伤逝
"Now his breath goes," and some say "no"
叹其气绝魂离，亦又说不然
So let me melt, and make no noise
就让我们悄然别离，不要喧哗
No tear-floods, nor sigh-tempests move
不要泪涌如潮，不要凄声叹息
They were profanation of our joys
那是对我们欢乐的亵渎
To tell the laity of our love
向俗人宣示我们的爱‌

这首诗通过细腻的情感描写和深刻的哲理思考，展现了离别时的复杂情感和对未来的豁达态度。