It's not every art exhibit that challenges the viewer to take on gravity and watch out for entropy. The return of miniature golf to the Walker Art Center, as part of this summer's celebration of the Minneapolis Sculpture Garden's 20th anniversary, promises to engage visitors in new and different ways. Golfers must pedal a stationary bike backwards, operate an oversized pinball machine and putt around bisected bowling balls -- and that's just on one hole. Meanwhile, across Vineland Place, an exhibit titled "Design for the Other 90%" features creative responses to human needs in the developing world, such as a water barrel shaped like a tire for easy transport.

So, on one side of the street, the intensely practical; on the other, the entirely frivolous. But on both sides, demonstrations of the role of design in human life -- and of the value an institution like the Walker brings to a city.

A lesson for schools A Minnesota Department of Education review found that the Tarek ibn Ziyad Academy (TIZA) charter school in Inver Grove Heights did not improperly use tax dollars to promote Islam. The investigation, which was prompted by media reports, concluded: "There were no concerns with respect to the law's requirement that operations be non-sectarian," and that "most of TIZA's operations are in compliance with state and federal law."

However, the state did identify two lesser areas of concern and called for corrective action. Evaluators questioned the practice of releasing students for 30 minutes every Friday (Muslim holy day) for voluntary, nonschool-sponsored prayer. That amount of time may take away from state-required instructional hours and should be done at another location. Also, bus transportation should be available earlier for students who do not participate in independent, after-school activities that include religious studies.

Worries that the school was somehow anti-American or inappropriately teaching religion should be laid to rest. Still, it should serve as a reminder to charters not to blur the line between accommodating and endorsing religion.