Sugar gliders are colony animals and do require changing interaction to stay mentally healthy. They are also hunting animals and require alternative stimulus when caged to maintain mental health. This is why environment enrichment is very important to their well being. This article is a list of ways to enrich your pet's environment.
CAGE
You should have the largest cage possible to house sugar gliders. Wild suggies will travel great distance in a night of hunting and play. Space is needed for leaping and exercise and mental interest. It is well known that sugar gliders kept in small bird cages are much more prone to health and mental issues.
EXERCISE
Much like most kept small animals, sugar gliders need exercise. To attempt to supplement what they are missing by being caged, exercise wheels are super important. It is recommended to have two 11"+ exercise wheels in every cage, even if there is a single glider.
BOXES and TUBES
Sugar gliders love to investigate things. You can help generate interest by inserting a new cardboard box into the cage nightly or often. Your suggie will sniff all over it and mark it and hide in it. Sometimes males will chew on a box as an outlet for mating angst. Paper tubes are good items for play as well. Be cautious of gliders who may chew on/eat cardboard, as there have been cases where ingested cardboard led to intestinal blockage.
FOOD
In the wild sugar gliders have to search for their food, so if you can move the food around the cage nightly, this can also keep their mind active. This is done at most zoos and is a form of environment enrichment. You could also hide bits of food in places ie. put tiny holes in a branch and place bee pollen for the glider to dig out.
If you use actual branches in the cage (make sure to research which ones are safe) you can spear fresh fruit on the ends of them for added foraging. Apples, bananas, and grapes (be sure to research the use of grapes in diets before making the decision to feed them) are all good foods for this type of enrichment.
HIDING PLACES
You can hide treats in foraging balls or inside other toys. This is a great type of enrichment, and causes them to 'hunt' and 'forage' for their food, just like they would have to do in the wild. Yoggies or nuts are great treats to hide in the cage, and use the smallest pieces possible. You can also buy puzzle feeders which cause the glider to use their brain and hands to get the treat.
CAGE ACCESSORIES
A safe and cheap way to creating an interactive space for gliders is by using various fleece cage accessories often referred to as cage sets. Long braided ropes, tassels, hammocks, bridges, pouches, etc. are used for lounging, climbing, nesting, sleeping, landing, or play by gliders.
TOYS
Think what a small monkey (marmoset or the like) would like and this is what would be good for a glider. Baby toys such as fisher price or plastic barns/airports/princess castles are lots of fun, and baby rings that link can be fun bridges. Straws and milk lid rings (that are cut so that they can't trap a glider in them) are fun, safe, and cheap toys. Bird toys and cat toys (that do not have catnip which is lethal for gliders) are also fun. Barrel of monkeys and other small toys (such as army men) are good for their little hands and tails, and you can sometimes watch them carry them around their cage with their semi-prehensile tail. Also plastic flowers and vines simulate a natural environment, add beauty to your cage, and are a lot of fun for the gliders!
WHEELS
Every glider cage should have a safe wheel in it, preferably one per every two gliders if space permits. Safe wheels are ones that will not injure the tail or feet, they will also not collect feces/urine, and cheap rodent wheels are dangerous. Review the types of wheels designed for sugar gliders: Exercise Wheels
PLAY OUTSIDE OF CAGE
Tent time, supervised exploration, out of cage time, bathroom time, glider proofing...
Always make sure that your glider is let out in a glider proofed room or tent. Make sure they do not have access to other animals, to open sources of water, to electric cords, to open sources of heat or cold, and most importantly make sure they can not get into a wall or small enclosed space.
You can bring treats, wheels, and toys into your play areas, and a lot of people love to use feather teasers for play time.
*EDIT NEEDED* Play Page is almost identical to this page. Although this page is written better.