On Friday, keep it relaxed. Your friends have probably been travelling for a while that day, so you want to have a low-intensity evening. One good option is going to The Gate: with an abundance of restaurants and entertainment options, you can’t go wrong. My personal combo is the arcade and Pizza Hut, but there's something for everyone - a cinema, Spoons, and more.
On Saturday, you have the whole day to experience the city. You could have a relaxing start to the day by going to a museum or taking a leisurely stroll through Jesmond Dene and stopping by a café. Shopping is always a good option – you can either go to Eldon Square or hop on a train to the Metrocentre, giving you the chance to experience the chaos of Northumberland Street or see beautiful views of the Tyne from the train. Then, in the evening, you have the chance to experience Newcastle’s nightlife. I came from a small town with no options for a good night out – so the change to a big city was so much fun. You have so much variety to suit everyone’s tastes; your friends might want a cheesy pop night or something more intense, and there's endless options.
Finally, on Sunday, you might need another slower-pace day. Assuming your friends are leaving that day, it’d perfect to visit the Quayside Markets, which gives you something to do in the morning and leaving the afternoon for travel. You’ll get to try some different foods, pick up some little souvenirs and take a lot of photos of the Glasshouse and the Tyne Bridge!