Hard as OAK > Returning in 2020 'teen OAK' is a 5km obstacle course challenge for you folk that are not quite 18. 11 - 17 year olds teenOAK will return in 2020! mini OAK is a 2km obstacle course challenge for the smaller folk! 6 - 10 year olds miniOAK returns in 2020! FAQ's Your questions answered. FAQs Downloads Parental Consent form Minor's Group Sign Up T's and C's Minor's Terms and Conditions Parents take note All participants need to be registered by a parent/guardian or as an organiser of a group you need to gain consent from their parent/guardian. To help organise a group and get the correct permissions please use the downloads above. If you are 16 or 17 years old you can also take part in the main 10km HaO event but only if you have a chaperone (18 or older) participating also, this a one to one ratio. For our mini OAK event, as an adult you have the option of jogging along (free) with your 'mini'. If you are doing this you need to register yourself with your minor.