Take your students for a walk in your neighborhood with the following questions in mind:
What types of trees are growing? What signs of wildlife are in, around, and under different trees? Which trees seem to be thriving and why? Which trees are native to or grow naturally in this area?
(You may have to consult a specialist at a nursery, Cooperative Extension, or state forestry office.)
Here are some other factors to consider:
What final tree height is most appropriate for the site? Do we want deciduous trees or evergreens (e.g., conifers)? Showy flowers? Fruit? Shade or wind protection? Which spot has sunlight and easy access to water? Are there underground utility lines we must avoid?
Dig a hole the same depth as the root ball or container and two to three times the width.
Loosen the sides of the hole so the roots will be able to spread out as they grow.
Lift the tree by its root ball into the hole so the crown (where roots meet trunk) is 1/2 to 1 inch above the soil surface. (Remove any wires and fold burlap down into the hole.)
Partially fill the hole with soil, tamp it to eliminate air pockets, and continue filling it.
Slowly add 3 to 8 gallons of water, then add 4 to 6 inches of mulch chips to keep down weeds, leaving the trunk open to the air to prevent rot. Continue watering the young tree when the soil feels dry 2 to 3 inches down.
If you plant bare-root trees, first soak the roots overnight, cutting back broken ones to healthy tissue. Make sure your hole will accommodate the root length, then make a pile of soil in the middle so the crown will settle at grade level. Spread the roots over the pile before continuing to fill and tamp.