For the start of the school year I find these two prayers from the book Prayers of the Reformers (complied by Clyde Manschreck, London: Muhlenberg Press, 1958) fitting.
For scholars (M. Coverdale)
O God, thou that of thy grace and fatherly love hast given such good and excellent gifts with singular light in all sciences; grant unto such as be learned a heart and mind that in all things they may have respect only to thy glory, and that in all their readings, writings, teachings, and doctrines they may prefer the same. For ‘knowledge puffeth a man up, but love edifieth.’
O suffer not thy holy and excellent gifts to be stained, defiled, and marred. Grant that our studies be not heathenish but godly and Christian. Preserve the tender and good youth from wicked and ungodly schoolmasters; that the pure hearts which thou hast consecrated to be a temple for thee and thy Holy Spirit be not defiled with vice. Amen.
On preparing to go to school (J. Calvin)
O Lord, who art the fountain of all wisdom and learning, since thou of thy special goodness hast granted that during our youth we be instructed in the good arts which may assist us to honest and holy living, grant also, by enlightening our minds, which otherwise labor under blindness, that we may be fit to acquire knowledge. Strengthen our memory faithfully to retain what we have learned: and govern our hearts, that we may be willing and even eager to profit, lest the opportunity which thou now givest us be lost through our sluggishness. Be pleased to infuse thy Spirit into us, the Spirit of understanding, of truth, judgment, and prudence, lest our study be without success, and the labor of our teachers be in vain.
In whatever kind of study we engage, enable us to remember to keep its proper end in view, namely, to know thee in Christ Jesus thy Son; and may every thing that we learn assist us to observe the right rule of godliness. And seeing thou promisest that thou wilt bestow wisdom on babes, and such as are humble, and the knowledge of thyself on the upright in heart, while thou declarest that thou wilt cast down the wicked and the proud, so that they will fade away in their ways, we entreat that thou wouldst be pleased to turn us to true humility, that thus we may show ourselves teachable and obedient first of all to thyself, and then to those also who by thy authority are placed over us. Root out all vicious desires from our hearts, and inspire us with an earnest desire to seek thee.
Finally, let our only aim be so to qualify ourselves in early life, that when we grow up, we may serve thee in whatever station thou mayest assign us. Amen.