The Australian-born educator started the school with three students and one teacher, and now provides a free, high quality education to more than 1800 students.
Each year, the school accepts 150 new students based on their academic potential and genuine financial need, giving the gift of education to these students to equip them with the skills and confidence to become future leaders in their communities and break out of the cycle of poverty.
Given the school does not receive any financial support from the Tanzanian Government, it relies on the generosity of the global community.
For a long time, Methodist Ladies College (MLC) in Melbourne have been fundraising for the school and raised thousands of dollars each year which helps them to buy vital resources and equipment for their classrooms.
Malcolm Davis from MLC says the school was so impressed with Sisia's work that they initially decided to commit some funds and support their teachers. They now run a study tour to the Tanzanian school each year and the girls involved in the tour spend the year raising funds to take along with them.
"So they virtually have a year's program which involves a lot of fundraising activities but also learning about Tanzania and learning specifically about The School of St Jude," Davis says.
Sisia says the money raised goes directly towards the most needed things or projects for their school.
"The goods we receive go to our resource centre and one of our staff looks after it and distributes them to the three campuses whenever they are needed," Sisia says.
"We will soon be purchasing a new bus to cater for an increasing number of students and we will also look into buying more computers and solar panels for hot showers at our boarding dorms."
To raise the much-needed funds, MLC runs a range of fundraising activities throughout the year including holding a store at a local market, a barbeque day and several casual clothes days.
Davis says each year the school raises around $10,000 for the Tanzanian school but they also donate equipment as well. The study tour students always dedicate at least half of their luggage to carrying science and maths equipment for the African school. Some MLC students are so touched by their travels that they also commit to sponsoring a student, which is a commitment of around $1000 each year.
"It is heartening when a school in Australia, or elsewhere, sponsors a St Jude's student and shares in their journey of learning," Sisia says. "Sometimes, a class will write to their sponsored student and then our student will write back to the class and give them an update about themselves and what they've been doing at school."
Next year, the first set of St Jude's students will graduate from the school and will be required to do a year of community service before the school supports them going to university.
"Ultimately, we want to instill in them a sense of giving and passion to get educated so they can become future leaders and help their country. With the knowledge they have already learnt, the students often go back to their villages and share what they have learnt with their siblings or other children," Sisia says.