The amazing thing about building with craft sticks is just how strong a construction you can make. The trick is to build with triangles. This way the structure is bolstered through a combination of tensile and compressive strength and the weight is spread out across the structure without putting excessive strain on the joints. Building this way, you can easily construct a bridge from craft sticks that can take weights of 50 lbs. or more.
Lay three craft sticks down end to end. Line them up with a ruler to keep them straight. Lay four more on top of the others, but overlap them so the join between the sticks in the bottom layer is in the middle of the layer on top.
Glue the first two layers together. Place another layer above the second. Overlap and glue the third layer in the same way you glued the second to complete the first beam for your bridge. Place a brick on top while it dries. Make three more beams for your bridge in the same manner.
Lay two of the beams parallel once they are dry. Join them with a zigzag line of craft sticks in which each stick joins at one end to the first beam and at the other end to the second. Make equilateral triangles in this way, then glue them in place and put bricks on top while they dry. Do the same with the other two beams. These make the two sides of the bridge.
Stand the two sides of the bridge up when dry and position them parallel to each other. Lay craft sticks between the two lower beams to form the road. Cut off the rounded ends before laying them. Glue them in place.
Lay more sticks between the top beams. Position them at as steep a diagonal as possible. Glue them in place and again use the bricks to make them dry tightly in those positions.
Position the bridge between two chairs or tables, where each chair or table supports one end. Gently lay the 50-lb. weight on top of the bridge, exactly in the center. The bridge should maintain its structure against the strain.