The American Heritage Dictionary defines the term “to apply oneself” as follows:

To devote (oneself or one's efforts) to something. Example: “applied myself to my studies.”

Saleh Ayyub’s translation is right on target. BATHALOO JAHDAHUM.

بَذَلُوا جَهدَهم

JUHD and MAJHOOD are fairly recent.

“Diligence” is defined as “earnest and persistent application to an undertaking; steady effort; assiduity, attentive care; heedfulness.” Al-Mawrid suggests KADD, IJTIHAD, or even “INAYA

كَـدّ، اجتهاد، عناية

“To sustain” is defined as “to keep in existence; maintain.” The adjective “sustained is often used in the sense of “kept up over a period of time.”

I am citing all of these definitions to demonstrate that the phrase is cleverly redundant. Applying oneself already implies diligence, which, in turn, already implies persistent effort. In other words, the phrase basically says that the principals must have sufficient evidence that the students have “exerted persistent effort with persistent effort and persistent effort.”

You should therefore not be surprised if the translation sounds redundant, although you should try to camouflage the redundancy as cleverly as you can. There are many tricks that writers, editorsma and translators use for this purpose that I will demonstrate below. The most common is to use near synonyms, but perhaps the trickiest trick is to alternate affirmative and doubly negative statements. Wherever it says the student ought to “do,” you can say the student should “not fail to do.”

A “task” is defined as “a piece of work assigned or done as part of one's duties. In most Mid-Eastern Arab countries, teachers and students call assigned work WAJIB واجب

“Experiences” in this context is a technical term from modern educational theory (See John Dewey, Democracy and Education, and Alfred North Whitehead, The Aims of Education). It refers to the aspect of learning by exposure and involvement, especially sensory experience, rather than memorizing definitions and abstract formulas. Arabs call such educational experiences KHIBRAT or TAJARIB.

خبرات أو تَجارب

Unfortunately, KHIBRAT is often used for expertise, and TAJARIB is used for experiments. Use your judgment here.

Roum’s translation of “school course” is the best. MUQARRAR DIRASIYY or MADRASIYY or TA”LEEMIYY

مُقَـرَّر دراسيّ أو مَدرَسيّ أو تَعليميّ

The translation of the phrase between quotes will depend on whether you wish to use the singular or plural. I will use the plural to fudge the gender issue. Here are a few possibilities with which you can start:

بَذَلُوا جَهدَهُم دُونَ تَقصير أو توانٍ في أداء واجباتهم واكتسـاب الخبرات المتاحة لَهُم في المقَـرَّر الدراسيّ
بَذَلُوا قُصارى جَهدهم دُونَ توانٍ في أداء واجباتهم واكتسـاب الخبرات المتاحة لهم في المقَـرَّر الدراسيّ
بَذَلُوا من الجَهد غايَتَه دُونَ توانٍ في أداء واجباتهم واكتسـاب الخبرات المتاحة لهم في المقَـرَّر الدراسيّ
بَذَلُوا وسعَهم واجتَهَدوا دُونَ توانٍ في أداء واجباتهم واكتسـاب الخبرات المتاحة لهم في المقَـرَّر الدراسيّ
لم يَتَوانوا أو لم يُقَـصِّروا أو ما قَـصَّرُوا سَعياً واجتهاداً في أداء واجباتهم واكتسـاب الخبرات المتاحة لهم في المقَـرَّر الدراسيّ

Fuad