Introduction: School Bag Trolley

About: I'm Utkarsh Kumar Gupta, an engineer, artist, inventor, focused on sustainability issues. My true passion is creating functional products integrated with technology. I'm interested in new technologies and the …

A local NGO invited me to their space to show school going girls on how to plan and make a utility project.

NGO - Feminist Approach to Technology . Their mission is to empower women by enhancing women's awareness, interest and participation in technology and they do it by teaching and training underprivileged girls using STEM approaches breaking societal stereotypes and attitudes, encouraging and enabling women to feel capable and comfortable in working with technology.

Now the task was to make something which can be made in a 6 hour workshop, have a societal impact and something which can solve one of the basic problems of these girls.

So I came up with this idea to get all girls write one of their most common problem on a piece of paper and put all those in a box and randomly select one. If the selected problem is common to more than half of the girls then we will make something to rectify that problem.

We did the same and got the problem statement which was, “school bags are too heavy to carry”.

Now the school they study in is about 3-4 miles away from their locality and majority of them have to cover that distance walking.

All they need was little encouragement and guidance.

Step 1: Material & Tools Used


  • 18 mm Block Board
  • 12 mm Plywood Sheet
  • 10 mm Self Tapping Screws
  • M5 Nut Bolts
  • 32mm Nails
  • 1"X1" Aluminium Angle (1/16" Thickness)
  • Nylon Trolley Wheels
  • Wood Glue


  • Center Punch
  • Hammer/Nail Gun
  • Drill Machine
  • Jigsaw or Circular Saw or Handsaw
  • Screw Driver

Step 2: Learning Basic Geometry Shapes

Geometry helps us in deciding what materials to use, what design to make and also plays a vital role in the construction process itself. We started with learning geometry to come up with trolley design and by the end of the workshop we had 18 trolleys for heavy bags planned, designed and made by girls themselves.

Circle, Triangle, Square and Rectangle are four basic shapes we learned about.

Step 3: Circle

A circle is a round shaped figure that has no corners or edges. In geometry, a circle can be defined as a closed, two-dimensional curved shape.

The distance across a circle through the center is called the diameter. The radius of a circle is the distance from the center of a circle to any point on the circle. Thus, the diameter of a circle is twice as long as the radius.

A circle (black), which is measured by its circumference (C), diameter (D) in cyan, and radius (R) in red; its center (O) is in magenta.

We can look at a pizza pie to find real-world examples of diameter and radius. Look at the pizza on top which has been sliced into 8 equal parts through its center. A radius is formed by making a straight cut from the center to a point on the circle. A straight cut made from a point on the circle, continuing through its center to another point on the circle, is a diameter.

One most common example of circle is a wheel which we are using in Bag Trolley. Now these wheels must be strong enough to withstand the weight of trolley as well as bag with all books, lunchbox and other items contained in the bag.

Step 4: Triangle

A triangle is a shape formed when three straight lines meet. All triangles have three sides and three corners (angles). The point where two sides of a triangle meet is called a vertex.

A right triangle, (also called a right-angled triangle), has one angle that is 90 degrees. The other two angles always add up to 90 degrees but can be different sizes. The side opposite to the right angle is the hypotenuse; it is the longest side in the right triangle.

Step 5: Rectangle

A rectangle is a shape with four sides and four corners. The corners are all right angles. It follows that the lengths of the pairs of sides opposite each other must be equal.

The word comes from Latin words meaning "right" and angle". Rectangle being the most common shape forms a part of our day to day life.

Some real-life examples of the rectangle are table tops, books, mobile phones, TV, etc.

Step 6: Square

A square is a shape with four equal sides and four corners that are all right angles (90 degrees). The diagonals of a square also cross at right angles. The angle between any diagonal and a side of a square is 45 degrees. A square with vertices A, B, C and D is shown above.
Here AC and BD are two diagonals of the square. ABC and ADC are two right angled triangles.

A square is a type of rectangle with all sides of equal length. However, while a square is a type of rectangle, the opposite does not need to be true.

Step 7: Design

Now all the shapes learnt are well used up in this design. It consists

Nylon wheels that we are using in the trolley is the real life example of circles. These are shown in yellow color in diagram.
We have used three rectangular cut outs as indicated in the diagram above R1 R2 and R3.
Top one R1 to provide structural stability, R3 in bottom and R2 adjoining R3 vertically.

A wooden plank cut in right angled triangle T shape is used to fix R2 and R3 together.

Step 8: Making

That that we have a simple design in our hands, its time for hands-on tools.
We started with with marking plywood so as to get our shapes planning in a way such that we can utilize as much as we can.

  • Now width of Rectangles R1 R2 R3 are same while height is different for all three so using a circular saw I cut out complete length of the board. Circular saw is a heavy tool so we taught our girls to use a jigsaw.
  • Girls did a brilliant job and one by one they came, they learnt, they cut under our guidance (me and volunteers) and all had 3 Rectangles by the end of this step.
  • For cutting triangles we first cut out squares, each girl made one square of their own. Now cutting a square diagonally gave us two right angled triangles T.
  • Now that we had all the pieces its time to assemble. We first joined R2, R3 and T on both sides. This is done using wood glue and brad nail gun.
  • We then used power screw driver to fix two wheels on the bottom.

Time to use Hacksaw/Handsaw, Aluminium angle that we are using to keep all things together came in length of 10' each and our required length was two units of 2' and 1 units of 1'2". So we cut out all the aluminium angles required for making these trolleys.

  • Now we again grabbed power screw driver and fixed bottom part(R2+R3+2XT) as well as R1 on aluminum angles. This is done using self threading screws.
  • To make handle we use 1'2" Aluminum Angle and joined it using Nut bolts on the end of the 2' units

Voila!! The trolley for bags are ready.

Step 9: Happy Ending

It took two 6 hour sessions to make 18 bag trolleys. It admittedly took longer than I thought but seeing the happiness of kids in the end it was well worth it. I hope you guys like it :)

I went back a few weeks later for another workshop and was blown away seeing more of such trolleys they made on their own which now they were using not just to carry their school bag-packs but also for carrying water buckets, as well as other heavy weights.

If you like it please vote for this Instructable. :)

Step 10:

STEM Contest

Participated in the
STEM Contest