The summer break is well underway. The weather is warming and kids are getting used to some time away from school.

Parents, meanwhile, are trying to find ways to keep the kids entertained over the break.

Chances are you remember your own childhood summers full of adventures outdoors in some plot of green near your home. Perhaps you had cubby houses or made cakes out of mud or just ran around seeking shade under the nearest tree.

For this generation, not only have changes in families' lifestyles resulted in children spending much less time outdoors than in previous generations, but many children prefer to spend time indoors playing electronic games, rather than getting out in nature.

In fact, the majority of children spend more than the recommended maximum of two hours per day involved in "screen time". In a 2009 study, researchers found that over half of the Australian children studied between the ages of ten to 12 spent less than 1 hour outside each day.

But there are plenty of physical and mental benefits to outdoor time for children. Here are just a few reasons to get outside this summer.

1. Physical health

Research shows that children who play outside are more active and generally have a lower risk of childhood obesity due to higher levels of physical activity generally (how many children do you know that sit perfectly still outside?).

Also, children who take part in school veggie gardening projects develop more healthy eating habits, including making healthier food choices. Children are more curious about a variety of foods when they have watched them grow.

Interestingly, at least one study also shows that the more time a child spends outside, the lower their risk is for shortsightedness. An increase of about 45 minutes of outdoor time per day is enough to make a difference, which doctors suspect has to do with higher levels of light outside.

2. Immune system

Exposure to sunlight increases the body's natural production of Vitamin D3. Children who are outside create more of this vitamin, which is important for bone and muscle development. It is also beneficial for overall health, but balancing your sun exposure is particularly important during the summer months, so remember to use sun protection as needed.

Despite the old adage that going out in the rain will make you sick, growing up on a farm can protect children from allergies and asthma. A day out playing in the rain does not make you ill - the most important thing is to be sure children are adequately dressed.

3. Cognitive skills

There are many benefits of natural environments in relation to how children's brains work.

Research shows that being outdoors can lead to a range of cognitive benefits for children, including better memory, improvements in Attention deficit hyperactivity disorder (ADHD) symptoms, improved concentration, and better reasoning skills.

It is thought that exposure to nature plays a positive role in brain development by providing children with opportunities to take risks, discover new things, be creative, develop a sense of wonder and engage in new tasks.

4. Psychological state

Children can also benefit psychologically from being outdoors.

Research shows that exposure to natural environments can lead to a reduction in anger, a decreased risk for problem behaviour, greater respect for self and others, greater autonomy and a reduction in depressive symptoms.

Children's ability to regulate their emotions is also improved through exposure to nature.

Attention Restoration Theory (ART) is one explanation for how exposure to nature helps children psychologically. It is thought that modern life requires extended periods of concentration, which leads to mental fatigue. This can make a person irritable and easily distracted. Exposure to nature, however, can help to repair this mental fatigue and restore a person's wellbeing.

5. Wellbeing

Children's general wellbeing can also be helped by exposure to nature.

Studies have found that even the simple presence of nature (trees, grass, plants) near children's homes can help children better cope with stress.

It also seems that spending time in nature can have long lasting benefits into adulthood. Research shows that children who spend more time in nature grow up to feel more connected to nature and have more positive attitudes about environmental sustainability.

The stress reduction theory offers one explanation for the impact of nature on children's wellbeing.

Research shows that being in a non-threatening natural environment reduces the body's stress reaction. The natural environment triggers the body's relaxation response, where blood pressure, heart rate and cortisol levels are reduced.

So, this summer get your kids out to a park, go on a long nature walk, or simply have them go play outside in the garden for a few hours. It really is good for them.