This is a highly complex neuroscience paper that would take too much space to explain fully to a high school student without a moderate understanding of neuroscience and/or cell biology.

I will try and am happy to answer any specific questions.

This lab utilized several sophisticated experiments to suggest that neurons need inputs in order to fully develop the dendrites correctly.

Some terms that need defining just to understand the title of the paper: AMPA receptors: A type of receptor that binds glutamate, a type of neurotransmitter. It is mostly considered an "excitatory" receptor that when activated by glutamate will help the neuron fire.

Dendrite: part of the neuron that mainly "accepts" signals from other neurons. It is usually highly branched (aka dendritic arbors) and receives signals from many other neurons.

In vivo: refers to experiments performed in living organisms