"educational robotics for students up through age 19"
Does this mean from age 1-19?
Does this mean 19 and onwards?
Does this mean only for 19 year olds?
Something similar posted elsewhere but it wasn't much help for me.
It means students age 19 or younger. The "through" indicates to me that age 19 is included in the range. If the expression were "up to age 19", I would interpret that as students under the age of 19.
Here is an example where the meaning of "up through" is explained in the next sentence to make sure it is clear:
All children up through age 18 are eligible for nutritious breakfast and lunch meals at no charge. There is no application necessary and any child age 18 or younger can simply come during meal times to receive a free meal.
Even native English speakers sometimes have trouble interpreting expressions about ranges of values precisely. Often it isn't clear whether the last value of the range is included or excluded. For example:
What does "up to age 14" mean to you? Does it mean day after the 14th birthday or through 14th year to day before 15th birthday. Our dental insurance pays 100% of a service "up to age 14"...
(From a forum post on another site)